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ADAPTIVE FLOATING SETTLEMENTS An Investigation to integrate strategies of wave height reduction and aquaculture activity to develop organizational logics of floating settlements

YuTao Song (MSc) Patrick AndrewTanhuanco (MSc) Panit Limpiti (MArch) Hung Wen Tseng (MArch) Emergent Technologies and Design Graduate School 2014-2015 Architectural Association School of Architecture


ARCHITECTURAL ASSOCIATION SCHOOL OF ARCHITECTURE GRADUATE SCHOOL PROGRAMMES

Emergent Technologies and Design 2014-2015

MSc Dissertation 2015 - Adaptive Floating Settlements Tutors: Michael Weinstock, George Jeronimidis, Evan Greenberg, Mehran Gharleghi, Manja van de Worp Declaration: ‘We certify that this piece of work is entirely our own and that any quotation or paraphrase from published or unpublished work of others is duly acknowledged.’

Yutao Song (MSc)

Patrick Andrew Tanhuanco (MSc)

Panit Limpiti (M.Arch)

Hung Wen Tseng (M.Arch)

Submitted: September 18, 2015


ADAPTIVE FLOATING SETTLEMENTS An Investigation to integrate strategies of wave height reduction and aquaculture activity to develop organizational logics of floating settlements

YuTao Song (MSc) Patrick AndrewTanhuanco (MSc) Panit Limpiti (MArch) Hung Wen Tseng (MArch) Emergent Technologies and Design Graduate School 2014-2015 Architectural Association School of Architecture


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ACKNOWLEDGMENTS Our deepest gratitude to all who supported us and provided the means to be part of the Architectural Association’s Emergent Technologies and Design graduate program. To our families, friends, colleagues for their continuous prayers, encouragement, and source of competitive inspiration. To our tutors who patiently helped us develop this dissertation through their guidance, constructive criticism and encouragement. To our M.Arch team mates, Felix and Ip, for helping us in every step of the way. May you carry this project and develop ideas further in the next phase! Yutao Song & Patrick Andrew Tanhuanco

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CONTENTS Abstract Introduction 1.0 Domain 1.1

Overview

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1.2

Existing Floating Settlements

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1.2.1 1.2.2 1.3 1.3.1 1.3.2 1.3.3

Floating Villages Aquaculture Hydrodynamics at Coasts Sea Waves Tides Storm Surge

1.4 Research Context 1.4.1 Xiapu County, Fujian, China 1.4.2

Existing Aquaculture Industry

1.4.3

Contextual Conditions

1.5 Research Proposal 1.5.1 Research Ambition 1.5.2 Design and System Ambition 2.0 Methods 2.1 2.2

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Process Tools and Techniques

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53

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4.0 Design Development

3.0 Research Development 3.1

Analysis

3.1.1

69

Principles and Parameters

3.1.1.1 Coastal Biological Systems 3.1.1.2 Man-Made Coastal Structures 3.1.1.3 Conclusions 3.1.2

3.2

Test Site Information

3.1.2.1

Context and Hydrodynamic Conditions

3.1.2.2

Precedents from Site

3.1.2.3

Conclusions

Experiments

3.2.1

Porosity Experiment

3.2.2

Density Experiment

3.2.3

Conclusions

3.2.4

Wave Reduction Simulation Experiments

3.2.4.1

Testing LBM Method

3.2.4.2

Wave Impact and Platform Arrangement

94

4.1 4.1.1 4.1.2

Basic Unit Research Generative Form Finding

4.1.3 4.1.4

Adaptive Wave Reduction Unit Morphology Unit Clustering and Mooring Strategies

4.1.5

Potential Floating Public Platform

4.1.6

Wave Reduction System Context Adaptation

4.2

105

Wave Reduction System

Floating Settlement Organization

4.2.1

Network

4.2.2

Zoning and Program Distribution

4.2.3

Settlement Aggregation and Density Distribution

4.2.4

Adaptive Floating Settlement Organization

5.0 Evaluation and Further Developments Bibliography

3.2.4.4

Appendix

3.2.4.5

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159

178

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3.2.4.3 Considering Wave Equations & Relationships Improved Clustering and Wave Reduction Algorithm Conclusions

134

195

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ABSTRACT Adaptive

Floating Settlements is a dissertation that investigates on integrating different strategies to address wave energy reduction and develop organizational logics of floating settlements centered around the aquaculture activity. This is in response to the compound effects brought about by coastal migration, rapid changes caused by climate change and increasing demand for food. The research was contextualized in Xiapu County, Fujian China, where an existing aquaculture industry with floating settlements are thriving, but face vulnerabilities due to frequent storms bringing destructive waves that damage property and the lack of a system to address thereof, as well as the consequences of an ‘informal’ or self-organized settlement. Data on the site’s existing aquaculture, and socio-economic conditions were gathered, precedents such as existing wave attenuation system structures including coastal biological systems and man-made structures are analyzed to abstract principles and parameters to inform the development of design ambitions and strategies. Through experiments, development of analytical tools and algorithms, an integrated strategy was achieved where wave attenuation served as the major driver for pattern arrangements, followed by aquaculture and social logics to influence the development of an emergent and adaptive organizational logic for coastal floating settlements.

Keywords: floating settlements, adaptive, wave reduction system, settlement logics, pattern, aquaculture

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Opposite: Floating Fishing Settlement in Fujian China. Photo by Research Team

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INTRODUCTION Why look into floating settlements?

L

iving on the sea is not a new thing. Floating settlements have been in existence for hundreds, if not thousands of years. These settlements, typically villages, belong to seafaring people or those who depend on the resources from the ocean for their livelihood and sustenance. Most villagers even do not own their own land and spend most of their time at sea on their boats or floating houses. Built around tradition and knowledge passed from generations, often independent from government control, these villages are commonly ‘informal’ or unplanned settlements. Each individual family functions independently concerned with their own needs and sustainability. But on a larger scale, a seemingly ‘selforganized’ community emerges, enabling these floating villages to play an integral part in the global community security is concerned. of existing floating villages are often dictated by their livelihood activities and influenced by seasonal changes in the environment. How have these activities influenced the systems level of organization of floating settlements? Can these be combined with other strategies to develop a more responsive planning and organization of new and adaptive floating settlements?

Floating settlements can potentially be a solution to growing problems of rapid coastal migration and population growth, although the existing villages face numerous issues and vulnerabilities themselves such as social and environmental related problems. This dissertation does not aim to radically change or re-design the existing, but to investigate and develop innovative, adaptive strategies based around the available system logics of existing villages, allowing a progression or hierarchical development of settlement organization strategies such as dealing with the growing, most pressing problems of extreme weather In the next chapters and underlying sections, the research investigation begins with understanding what problems and environmental physics affect the scope of the project. A design ambition is set as hypothesis and driver for futher investigation. Through analysis and testing of methods and precedents, strategies are developed and tested using computational techniques. Can a system for settlement organization be developed to better improve the existence of floating settlements? And, can this study potentially serve as foundational basis for developing planned settlements on the sea in the future?

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1.0

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1.1

OVERVIEW Peru 4,807,923

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ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

USA 5,107,559 tonnes


India 3,402,,405 tonnes

China 13,869,604 tonnes

Population with in 100 km from coastline None Less than 30% 30 to 70% More than 70% coastal cities with more than 1 million ppl

26°- 36° Celsius Most altered shoreline Altered shoreline Tropical cyclone

Fig.1.1-1 Global overview of coastal population, climate change effects adapted and redrawn from various sources.

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1.1

OVERVIEW

Integrated Challenges As an overview of the project, this dissertation especially in developing countries and low-lying coastal communities. These are Coastal Population Growth, Climate Change, and Marine Ecology Imbalance. These three challenges are tightly integrated with factors or issues that have cause and effect implications to one another. Coastal Population Growth Many people are continuously migrating towards the coast and these settlements are fast becoming urban. The lure of economic and technological development, job opportunities, and access to resources contributes to the rapid urbanization of the coastal areas. According to Creel, L. (2003), already 14 of the world’s 17 largest cities are located at coastal areas and approximately 3 billion people or half of the world’s population already lives within 200km of a coastline, and it may likely to double by 2025. A growing population includes social, economic and nutritional requirements (Porter et.al,

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2014), and continued coastal development poses a threat in degrading coastlines and natural ecosystems that help provide for the requirements. Climate Change Coastal areas are very vulnerable regions particularly those in the tropical and sub-tropical regions (Fig.1.1-1). Adding to human-induced changes and degradation of the coastal areas, the compound effects of climate change such as the accelerated sea level and sea temperature rise bring about more frequent extreme weather events such as stronger storms and hurricanes, also increasing the risk of storm surges and inundation at coastal areas. These extreme events destroy properties; endanger life, livelihood and even damage coastal ecosystems such as coral reefs, and mangrove forests that should serve as protection and provider of changes occurring in the environment, the adaptive capacity of human settlements and natural ecosystems needs to be strengthened.


91% 91% 91%

Coastal development Coastal Coastal development development By 2050, 91% of the By 2050, By 2050, 91% 91% of world’s the of world’s the world’s coastlines will be by by by coastlines coastlines willaffected be willaffected be affected development. Average development. development. Average Average population density in coastal population population density density in coastal in coastal areas is areas 80ispersons/sq.km - - areas 80ispersons/sq.km 80 persons/sq.km double the world’s double double the world’s the average world’s average average population density. population population density. density.

Coastal Population Growth

63% 63% 63%

Coastal settlement Coastal Coastal settlement settlement

COASTAL SETTLEMENTS

21 of21the world’s mega-cities of21 the of world’s the 33 world’s 33 mega-cities 33 mega-cities 21 are of located the world’s 33 areas, mega-cities are coastal are located are in located in coastal in coastal areas, areas, located in coastal areas, most of them withwith most of most them inwith developing with most of them of them in developing in developing in developing countries. Poor planning countries. PoorPoor planning results Poor planning planning results results results countries. in countries. the loss of key ecosystems in the of key ecosystems in loss the in loss the loss ofmangroves key of ecosystems key ecosystems such as wetlands, and coral such asaffect wetlands, mangroves such such as wetlands, as wetlands, mangroves mangroves Coastal population reefs that marine resources coastal Coastal population Coastal population and coral reefs. and and coral coral reefs. communities rely on forreefs. livelihood.

91% 91%91%

COASTAL DEVELOPMENT Coastal development

Coastal development Coastal development By 2050, By91% theof the world’s 2050,of91% world’s By 2050, 91% of world’s By 2050, ofaffected the world’s coastlines will91% bethe by coastlines will be affected by coastlines will be affected by by coastlines will be affected development. Average population development. Average development. Average development. Average density inpopulation coastal areas densityisin 80 coastal population density inthe coastal population density in world’s coastal persons/sq.km - double areas is 80 persons/sq.km areas is 80 - areas is persons/sq.km 80 persons/sq.km average population density. double the world’s average double thethe world’s average double world’s average population density. population density. population density.

50% 50% 50%

52% 52% 52%

Exploited Resources Exploited Exploited Resources Resources

Coastal Protection Coastal Coastal Protection Protection

50%50% of world’s 50% of world’s of wetlands world’s wetlands wetlands disappeared in the Century are fully exploited and and haveand disappeared disappeared in 20th the in 20th the 20th Century Century are fully are fully exploited exploited havehave (50%(50% of mangroves, and and 60%and of coral toability produce greater (50% of mangroves, of mangroves, 60% 60% of coral of coral no ability no ability no to produce to produce greater greater reefsreefs arereefs degraded), these wetlands are degraded), are degraded), these these wetlands wetlands harvests. harvests. harvests. are critical providing coastal are critical areincritical in providing in providing coastal coastal protection fromfrom storm surges protection protection from storm storm surges surges

Climate Change

Marine Ecology Imbalance

20% 20% 20%

70% 70% 70%

Sea Sea levelSea Change level level Change Change

ILLEGAL FISHING

SEA LEVEL RISE

About 70% of the About About 70% 70% of coastlines the of coastlines the coastlines About are 70%projected of theto coastlines worldwide worldwide worldwide are projected are projected to to worldwide are projected to experience sea level change experience experience sea sea level level change experience sea level changechange within within 20% of the within within 20% 20% of global the ofmean global themean global mean mean 20% of the global sea level seachange level change at the end of sea sea level change change the atcentury. end the end of of at level the end ofat21st 21st21st century. Climate change 21st century. century.

Climate change Climate change

an estimated 20%20% of the an estimated an estimated 20% 20% ofthe the ofworld’s the catch estimated of world’s catch and as world’s world’s catch catch and and as as much and as muchmuch as much 50% in some

Marine biology imbalance Marine biology imbalance Marine biology imbalance

50% 50%50%

COASTAL PROTECTION

52% 52%52%

Coastal Protection Coastal Protection Coastal Protection Due to climate and human induced 50% ofchange world’s wetlands 50%50% of world’s wetlands of world’s wetlands degradation, 50% of inworld’s disappeared the 20thwetlands Century disappeared in the 20th Century disappeared in the 20th Century disappeared 20th Century of coral (50%inofthe mangroves, and (50% 60% of (50% of mangroves, 60% ofreefs coral (50% of mangroves, 60% of coral mangroves, and 60% and of and coral are reefs are degraded), these wetlands reefs areare degraded), these wetlands reefs degraded), these wetlands degraded), these wetlands are critical in are critical in providing coastal providing coastal protection from storm areare critical in providing coastal critical in providing coastal protection from storm surges surges, and habitats to nurture marine life. protection from storm surges protection from storm surges

EXPLOITED Exploited RESOURCES Resources Exploited Resources Exploited Resources fully exploited and have no ability to

are fully exploited and have produce greaterand harvests. areare fullyfully exploited have exploited and have no ability to produce greater no ability to produce greater no ability to produce greater harvests. harvests. harvests.

Fig.1.1-2

63% 63%63%

Coastal settlement Coastal settlement Coastal settlement 21 of the world’s 33 mega-cities 21 of world’s 33 mega-cities 21the of the world’s 33 mega-cities are located in coastal areas, areare located in coastal areas, located in coastal areas, with most of them in developing withwith most of them in developing most of them in developing countries. Poor planning results countries. Poor planning results countries. Poor planning results in the loss of key ecosystems

70% 70%70%

The Integrated effects in numbers.

20% 20%20%

Sea level Change SeaSea level Change level Change About 70% of the coastlines About 70%70% of the coastlines About of the coastlines worldwide are projected to worldwide areare projected to to worldwide projected experience sea level change experience seasea level change experience level change within 20% of the global mean within 20%20% of the global mean within of the global mean sea level change at the end of

an estimated 20% of the an estimated 20%20% of the an estimated of the world’s catch and as much world’s catch andand as much world’s catch as much

1.0

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1.1

OVERVIEW

Marine Ecology Imbalance

Conclusion

Coastal population growth pushes forward the development of coastal areas, and poor management and planning results in degradation of natural environments which support the growth and provision of marine resources. With increasing population, food security is threatened and must be addressed. Marine resources for seafood are heavily exploited to meet the ever increasing demand. When marine catch declined, aquaculture rapidly increased, and when not properly managed leads to pollution, affecting the envrionment. Porter et.al (2014) notes that human induced factors

This dissertation looks into the East Asia and South East Asia region where there is continuous population growth and increasing coastal migration and rapid urbanization. This region contributes to a large part to the global food production and supply for seafood. However, it is further threatened by the rapid changes of the climate and environment particularly the increase in frequency of storms.

impacts attributable to climate change, which overall aquaculture industry.

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attributed to the long term effects of human activities, climate change still plays a major role in integrating the effects of these challenges. It adds to the uncertainty of vulnerabilities, raising new concerns which current methods are considered ineffective to deal against with unforseen changes. While there is no direct control over when the sudden changes in the environment occur, the way or medium humans interact with their environment can be changed or improved. By increasing the adaptive capacity of coastal communities, it increases their resilience against the threats and changes brought about by climate change in the future.


1.2

EXISTING FLOATING SETTLEMENTS This section looks into two typologies - floating villages, and the aquaculture. These typologies exist in the coastal areas and serve as the interfaces where man and interacts with his environment. Although greatly affected by the rapid changes of the environment, coastal urbanization, and seafood supply demands, lessons can be learned from how these typologies have adapted to its environment over the years.

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1.2.1

FLOATING VILLAGES

Fig. 1.2.1-1 Koh Panyi Floating Village, Thailand Photo by Richard Barrow http://www.thailandfromabove. com/koh-panyi-floating-village/

Existence of Floating Villages Floating villages are located at lakes, bays and estuaries and even off-shore areas in many regions of East Asia and South East Asia. Many of these communities have already been existing for hundreds or even thousands of years, and are often developed based on the village location and livelihood source which more often but not Most of these communities are self-organized or informally growing without following a clear logic for arrangement and provision of facilities and infrastructure, in contrast to planned urban cities at the coasts which have a better structure, governing policy, and infrastructure provision. But they continue to function as a community. These villages either aggregate or grow from land, extending to the sea, with built infrastructure on stilts. Others are purely detached, with families living in boat houses, and even community buildings such as churches, schools, and even football pitches on floats. Interaction among villagers happen 20

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

from boat to boat, or on common floating platforms. However, these communities are often poor, and lack the proper facilities and services such as electricity, proximity to healthcare, fresh and clean drinking water, and proper sanitary services especially those who are located at the seas. While observing satellite images of these villages, it can be assumed that the location of these communities are also influenced by the geographical features of their environment. It also shows the extent of the scale of these communities. Existing Floating villages can be considered to have the have least intervention to their environments compared to other urban coastal developments. But even recent increase in population becomes unsustainable and affects the environment where they are situated. What can be learned from the existence of these floating communities? Can these community models be considered as a potential solution to address the impacts of coastal population growth, climate change


Fig. 1.2.1 -2 (Left) Floating Village in Tonle Sap Lake, Cambodia. (Right) Floating houses and boats in Halong Bay, Vietnam

and marine ecology imbalance? Or are they rather contributors to these impacts? A Model for Adaptive Settlements? It can be argued that these communities are generally well adapted to their environment and its seasonal changes, for example the floating village in Tonle Sap Lake, Cambodia is well adapted to flooding. But in the village’s adaptive capacity have limits and are more at risk to major and sudden changes in the environment such as extreme weather events, affecting the resources the environment provides as well. Also, they point to lowest capacity to cope with sudden or abnormal changes in the environment. Nuorteva, P. et.al (2010) notes that adaptation strategies in these type of communities are often at the scale of

an individual household (local), rather than at a regional or global scale such as village or community. Pender, J. (2008) suggests that priority should be towards using or modifying traditional coping mechanisms, and should be done in a local community level, rather than outsiderled interventions, which are often highly technical and Adaptation measures must allow the balance between local community’s self-organized methods and the more macro and long term policy responses. The adaptive capacity of floating villages depend largely on the livelihood sources (Nuorteva, P. et.al, 2010), and one of the good starting points for adaptation is the in the floating villages in Ha Long Bay, Vietnam, where communities have included tourism to complement activities and aquaculture, and their communities are developed around this activity. 1.0

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1.2.1

FLOATING VILLAGES - EXAMPLES N

N

200m

200m

100m

Case 1 | Tonle Sap Lake, Cambodia

clusters of villages along its edges. These villages are built on the flood plains of the lake, with populations ranging from 3,000 to 30,000 people. Houses and other village structures are primarily constrcted on stilts, with some at heights of 10 or more meters, while some are built on boats to accommodate the annual innundation of the lake caused by the fluctuation of the Mekong river water volume. Livelihood is also dependent on the seasonal flooding. Fishing is limited to times when flood waters start to recede.

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100m

Case 2 | Ko Panyi, Phnang-nga, Thailand

built on stilts, and is home to approximately 360 families, an estimated 1,685 people. The community is tightly clustered in one area compared to the villages around Tonle Sap Lake in, Cambodia. The mosque at the village serves as the focal point and gathering place for the community, and markets also exist and sell supplies from the mainland, such as medicines, toiletries and clothes. Wooden football pitch was also built, and a floating one more recently. Fishing is still the major source of livelihood, and tourism is effective during the dry season. As the population of the village grows, emigration is encouraged as the size of the village is limited for expansion due to the hazardous water conditions during rainy season.

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015


N

N

600m

200m

200m

200m

Case 3 | Ha Long Bay, Vietnam

Case 4 | Xiapu, Fujian, China

Named as a World Heritage Site by UNESCO because of its amazing landscape and geomorphology, Ha Long Bay,

Its existence of the Chinese floating village is known to have dated back to the Tang Dynasty (700AD). Throughout the Xiapu area, and particularly in Ningde

live in boats and wooden houses kilometers away from the mainland, but are more spread out and move around the bay continuously. Evident from the satellite images, the boats are positioned strategically behind islets, barrier islands as protection from potentially

bay areas, with their homes and aquaculture cages.It has approximately 7000 people, most of whom prefer to live their lives on the sea on their floating homes, barely touching land. Most villages are located in geographically protected areas such as bays, but some are in direct paths or exposed to waves. Contrary to other villages, the floating villages in the Fujian coasts are still expanding due to the increasing demand for seafood and aquaculture as a lucrative business. Modernisation is primarily on improving the homes and

and aquaculture. Adapting to the modern times, tourism industry has developed and controlled by the villagers

to these areas. 1.0

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1.2.1

FLOATING VILLAGES

Conclusion The adaptation of the individuals, to the community level of Floating villages is largely based on their own experience, observations, and economic capacity. However, due to climate change, the floating villages esepcially at areas that are developing, or poorer, are more vulnerable to shock, as they struggle to cope with the rapid changes of the environment particularly extreme weather events.

Fig. 1.2.1-4 Opposite: Aerial Photo of a Floating Fishing Village in Fujian, China Photo by Dissertation Team

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Thes floating villages in South East Asia, and East China, are good examples on how human settlements are well adapted to their surroundings, taking advantage of their location, such as the geomorphology for natural protection from harsh elements; using available resources for livelihood, and adjusting their processes and activities to the seasonal changes including the falling and rising of tides and flooding. Although these villages are not exepmted from other problems related to informal organizations, these examples can serve as a basis, or starting point for this dissertation in exploring, developing and rethinking potential solutions and strategies for adaptive coastal settlements.


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1.2.2

AQUACULTURE

Fig.1.2.2.-1 Seaweed Farm at China’s Fujian Coast. China is one of the largest producers and consumers of seafood by aquaculture. Photograph by George Steinmetz Adapted from How to Farm a Better Fish by Joel K. Bourne, Jr. www.nationalgeographic.com/foodfeatures/aquaculture/

The Practice of Aquaculture the rapid development of aquaculture. An increase plants and animals in all types of water environments,

must be produced by aquaculture alone to maintain

noaa.gov). It has two main types, marine aquaculture -which refers to culturing species that thrive in the ocean, and freshwater aquaculture - culture of species that are native to rivers and lakes. The former of which is the interest of this dissertation.

also report that projection of this trend will continue within the next 20 to 30 years minimum. As capture production declines due to environmental changes and impacts, affecting natural habitats, aquaculture is taken as the alternative, and perhaps now the leading source for seafood production (Fig.1.2.2-2). Porter et.al (2014)

Feeding the Growing Population The global population is projected to reach 9 billion by 2050. An increase in population means that production for food must also increase. According to Porter et.al (2014), three requirements of the continuously growing human population include social, economic and nutritional requirements, and these serve as the

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per person per year from a recorded total production of 148.5 million tonnes, 86% of which was used for human consumption. FAO reports (2012) a steady increase of 3.2 percent annually in world aquaculture production pacing world population growth.


Fig.1.2.2-2 Diagram illustrating the comparison production increase Diagram by Virginia W. Mason, Jason Treat, and Matthew Twombly, NGM Staff; Shelley Sperry Sources: FAOSTAT; Global Trade Information Services Adapted From How to Farm a Better Fish By Joel K. Bourne, Jr. www.nationalgeographic.com/foodfeatures/aquaculture/

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1.2.2

AQUACULTURE

Fig.1.2.2-3 Fish cage and house destroyed after Typhoon Souldelor swept through China’s Fujian Coast. Image Source: www.news.xinhuanet.com

Impacts on and by Aquaculture As reported in the Food and Agriculture Organization of the United Nations (FAO) 2012 State of World Fisheries and Aquaculture, it states that communities vulnerable to disasters. This is because of the location of the community, livelihood activities, and higher level of exposure to natural hazards, shocks and climate are always affected by variable climate, and effects of climate change are experienced through the increase in frequency of extreme events such as hurricanes, flooding and upwelling failure in oceans.

that affect the aquaculture industry particularly those at the sea, include storms and typhoons that bring about inundation, storm surges and tsunamis. These destroy important assets such as boats, cages, gears, post harvest and processing facilities, nurseries, and worst case, loss of life (FAO, 2010, 2012). It is important to note that damages by natural disasters have long term socio-economic impacts within and beyond the industry such as livelihood capacity and food availability, thus affected communities relying on aquaculture must be able to cope with these sudden changes. Adaptation and Resilience

Porter et.al (2014) states that climate change affects four dimensions of food security including the availability of seafood, stability of supply, access to seafood and utilization of aquatic products. They also suggest that communities will have to adapt

In addressing these issues, there is not one solution to address all problems, and adaptation measures the a community’s vulnerability - absorbing disturbance to the normal conditions, and their adaptive capacity the ability to retain basic functions and self-organize

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Fig.1.2.2-4 Satellite images from NASA showing Bo Hai, China’s coast. 1979 (left) and 2000 (right). It is considered to be one of the world’s highly intensive and exploited aquaculture regions

and build capacity for learning and to prepare for future impacts. From the circular FAO c.1088, they have as: investing in safer harbors and landings; Promote disaster risk management - general preparedness and protective infrastructure particularly on soft options such as buffer zones; and Spatial planning - marine and terrestrial zoning for siting of aquaculture facilities. Aquaculture Impacts on the Environment Another aspect worth considering is how aquaculture negatively impacts the environment. The practice is commonly confronted with issues such as environmental, coastal degradation, such as destruction and conversion of mangrove forests and wetlands into farms; pollution caused by waste excreted from cultured species; contamination water or land from disease management chemicals. (Barg.U, 2005, www. fao.org, www.landsat.visibleearth.nasa.gov). These

can be attributed to results from mismanagement of resources, driven by the need for rapid expansion or a more intensive production, or simply lack of organization. From traditional small scale production, to large scale intensive production, farms are managed at individual or household levels, even if farms coexist side by side. Initiatives must be done in a community and institutional level.

“A resilience perspective doesn’t focus on the ability of a system to resist change; instead it emphasizes the importance of disturbance, reorganization and renewal. The dynamic nature of the concept makes it useful when considering uncertain effects of climate settlements.” (Daw et.al, 2009)

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1.2.2

AQUACULTURE

Vulnerability

Potential Adaptation Measures

!

Anticipatory

Sea Level Rise

Hard/Soft Defenses

Infrastructure Provision

Rehabilitation and Disaster Response

Post-disaster Recovery

Early Warning Systems and Education

Managed Retreat/ Accomodation

Integrated Coastal Management

Response Timescale Storm Surge

Fig.1.2.2-4 Diagram illustrating the common vulnerabilities experienced by marine aquaculture community or industry and the adaptation measures in short and long term time scale. Based on Cochrane, K.,et al (2009)

Flooding

Reactive

Assisted Migration

Conclusion marine resources available the sea has to offer, there is more control on how much can be produced to meet source of livelihood for people living on the coasts, although majority of them reside in rural areas and in developing countries. While most aquaculture practices in the context of Southeast Asia and East Asia are traditional and at small-scale, and impacts to the social fabric and economy is minimal (Hishamunda, M., 2009), it is worth mentioning at this stage that the context of interest for this dissertation is at East Asia, China’s Fujian Coast, (more in section 1.4 - Research Context) where a large scale capital intensive aquaculture operation takes place. However, this area is heavily affected by extreme weather events such as stroms brining along high waves and surges. The settlements and aquaculture industry’s traditional methods and adaptive capacity are being

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tested. Although not to be the main focus of the project, but another question comes to mind and is worth considering - ‘how does the large scale aquaculture operation affect its environment and can organizing the settlement help develop reduce this impact?’ Therefore, given the examples of traditional floating villages, and the practice of aquaculture, this dissertation will focus on and further investigate on the potential of using these existing strategies to develop an alternative or new solution to integrating the planning of floating settlements and their livelihood activities to address the uncertainties of the extreme events brought about by climate change and the impacts of rapid growth.


1.3 HYRDODYNAMICS at COASTS This section briefly examines the hydrodynamic processes that affect the communities and their activities at marine coastal areas. Understanding the hydrodynamic processes and its parameters will be design ambitions and strategies. While the focus of the strategies will be more related to sea waves, other processes such as movement of tides and tide currents are basic considerations for site selection. More in depth study, application and testing of parameters are investigated on Chapter 3 and 4.

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1.3.1

SEA WAVES

Fig.1.3.1-1 Breaking Wave Energy of the wave is released when it reaches the point where the ratio of the wave height to its wave length is greater than 1/7. The wave becomes unstable and breaks

Developing Waves Atmospheric conditions delivered with a typhoon or a hurricane includes strong winds and heavy rains, and one of the destructive elements formed at the sea with storms are high waves and storm surges causing destruction and inundation when it reaches coastal areas. Waves acquire their energy by winds moving over the surface of the ocean. The transfer of energy from the wind to the surface of the ocean forms the waves. The height of the wave is determined by four variable factors: the wind speed, length of time the wind has been blowing, the ‘fetch’ or distance from which the wind has been blowing, and bathymetry or the topography of the seafloor. The greater the distance, or ‘fetch’ of open water the greater the amount of kinetic energy the waves possess (Weinstock, 2010). Waves at sea is not a movement of a substance such as sea water, but a pattern of behavior where energy is transported either overall transport of the material itself (S. Massel, 1999)

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Understanding how waves are formed and behave is important in managing and controlling coastal environments, such as beach erosion, sediment coastal structures (C.T. Hsu & Y.K. Law, 2005) either for coastal protection or to lessen the impact from damaging waves and surges. This section focuses more on surface waves, which floating villages and marine aquaculture community are experience the most.

Swells are also known as fully developed waves that are beyond the wind-driven waves or fetch area, they are more regular, traveling farther from the source and are ones that reach the shore.


WAVE GENERATING FORCES

Severe Storms Earthquakes, Volcanic Activity WIND

Sun, Moon

LIGHT

Wave Height (m)

101

CAPILLARY WAVES

STRONG

CHOP

SWELL

SEICHE

TSUNAMI

TIDE

100

10-1

Fig. 1.3.1-2

10-2

Idealized wave graph Orange box shows the scope of waves to be dealth with in this dissertation.

0.1 sec

1 sec

30 sec

5 min

12 hrs 24 hrs

Wave Period

20

15

10

Wind driven waves 5 Fig.1.3.1-3

0

0

3

6

9

12

15

Wave Height - Period Relationship Graph adapted and redrawn from Gerwick (1995), Fig.19, p.32

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1.3.1

SEA WAVES - PARAMETERS Crest

Crest

B

A Direction of Wave Propagation

Wavelength (L)

H

Still Water Level

Trough Fig.1.3.1 -4

Frequency

Basic Wave Parameters

Period

Wave Equations Deepwater Phase velocity (C)

Wavelength (L)

Intermediate

gT

gT2

gL

Lo

h L

tanh

tanh

Shallow

h Lo

gh

Lo

tanh

Wave height (H)

Ho function

Fig.1.3.1.-5

Limits of application

Wave Equations

34

h Lo

h 1 > 4 Lo

deepwater

h from 1 to 1 Lo 4 20

4

L

h 1 < 20 Lo

Parameters of Waves

Effect of Water Depth to Waves

Waves are characterized by their height, length and period (Fig. 1.3.1-2). The relationships of the parameters are important when understanding the principles for wave attenuation. Also, wave parameters are important

Wave characteristics are greatly affected by the bathymetry and other geographic conditions. As the depth of the water decreases, the interaction between

structures. For example, wavelength is the distance from one crest to the next crest. Given the wavelength, the depth of the wave structure can also be determined, which is often at 1/2 the wave length. The longer the wavelength, the deeper the reach or motions can be felt at the bottom of the sea (Fig. 1.3.1 -6a).

resulting in alteration of the wave properties, such as decrease in wave phase velocity and wavelength, and increase in wave height. Table of wave equations summarizes the interaction of wave parameters depending on the depth of the water. The ratio between the wave height (H) and wavelength (L) called wave steepness determines when the wave becomes unstable

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015


Water depth

Direction of Wave Propagation

L/2 Wavelength (L)

L/20

Water depth

L/2 Direction of Wave Propagation

Still Water Level Wavelength (L)

D= L/2

Still Water Level

Orbital Motion of Particles; Decreases with submergence Wave Base

Orbital Motion of Particles; Decreases with submergence

Seabed

(a)

Seabed

Wave motion - Shallow water Water depth

(b)

L/20 Direction of Wave Propagation Wavelength (L)

H

Fig. 1.3.1 - 6

Still Water Level

a) Deep Water Waves b) Transitional Waves c) Shallow Water Waves d) Transforming Waves from Intermediate to Shallow water Reference: Massel, R. 1999

Orbital Motion of Particles; Decreases with submergence Seabed (c)

starts to break and dissipate

Direction of Wave Propagation

(d)

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1.3.1

SEA WAVES

High energy and erosion

sediments)

Fig.1.3.1- 8 Wave Refraction Diagram at a bay area. Wave orthogonals theoretically perpendicular to the wave crests, these indicate the path and direction of wave energy either converging or diverging, which results in either erosion of the coast or deposition of sediments.

Wave Refraction The bending of waves and its change of direction as they approach near shore shallower waters or barriers such as islets is called refraction. Bathymetry plays a key role in influencing how the energy of the waves are dissipated or focused onto land, either causing erosion or deposition. Also, depending on the various factors that help develop waves, when conditions are right, the

Fig.1.3.1- 9 Diagram of Wave refraction caused by a rocky islet as viewed from the top. Some waves approach is parallel, some approach the beach area at an angle, contributing to longshore drift, responsible for sediment transport. Diagram Adapted from

36

A good example is off the coast of Half-Moon Bay, California, where the bathymetry (Fig.1.3.1-11) influences the refraction and convergence of waves, area can be as high as 24 meters.

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

indicate refraction


Fig.1.3.1 - 10 Aerial Photograph, with visible wave refraction over the bay, and an islet. Wave crests parallel the shape of the coastline. Photo by Greg Moore (used without permission). Source: www.coastalchange.ucsd.edu

Fig.1.3.1 - 11 Bathymetry Map of Half-Moon Bay, California. Rectangle indicates where wave refraction converges or focuses all the wave energy. Source: www.sanctuaries.noaa.gov

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1.3.2

TIDES

Fig.1.3.2 - 1 Tide range at Bay of Fundy, Canada can reach difference of 15m. At low tide (above), the bay can be completely drained, and boats rest on the ground. Image source: www.amusingplanet.net

Tide Causes and Importance Tides are caused by the attraction of gravitational forces between the Earth, Moon and the Sun. The position of the Sun and Moon relative to the Earth determines two types of tides, the spring and neap tide. Spring tides are caused when the moon is either in conjunction or opposition, resulting in higher high tides, and lower low tides. While neap tides produce smaller than average tide ranges. Tides are also considered as waves, with periods in order of 12 hours (Massel, R.,1999; Fig.1.3.1-2). Factors that affect Tidal ranges include latitude, bathymetry, shapes of the coastline and even weather patterns. Coastlines with long and shallow gradation, tides marks may be tens of meters apart in horizontal distance (www.oceanservice.noaa.gov), such as in Morecambe Bay, UK, where tide range as high as 10m and retreat as far as 12 kilometers. On estuaries, and bays, water may be funneled up through due to the articulated or unique coastal structures, greatly increasing the size of 38

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tide. Such extreme examples can be found in the Bay of Fundy, Canada (Fig. 1.3.2 -1) where the tide range can reach 15 meters. Tidal Currents Tides have two interrelated components, the vertical component - which refers to the rise and fall of the water levels indicated by the tide range, and the horizontal component -which considers the movement of water in and out of bays and estuaries, this occurrence is the the Flood current - when water from comes from the sea towards the shore (high tide) and Ebb current - when water flows from shore to the sea (low tide follows). This rising and falling of water levels and its direction of flows have been observed by sailors and coastal communities for thousands of years (Massel, R.,


Fig. 1.3.2 - 2 Tidal bore (wave generated at the leading edge of incoming tide) develops as rising tides flood in Morcambe Bay, United Kingdom

distance

High Tide Flood current

1999). Fishing communities have taken advantage of this phenomenon to strategically position their nets or improve their catch. For aquaculture, tide changes is locations of ports, and areas for other post-harvest processing activities and in considering the mixing and flushing of huge volumes of water carrying nutrients, sediments and/or pollutants. In building coastal structures, tide changes are monitored to develop

Ebb current

Low Tide

distance

High Tide Flood current

and effective designs in response to the fluctuating water levels.

Tide Range

Ebb current

Tide Range Low Tide

Fig. 1.3.2 -3 (BELOW) Diagram illustrating the horizontal distance of tide marks depending on the slope of the coastline. Also the vertical and horizontal components of tide.

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1.3.3

STROM SURGE

Fig. 1.3.3 -1 Destruction of brought about by storm surge that accomapnied Typhoon Haiyan 2013, Tacloban, Philippines. Houses were flattened and swept away, ships beached on land and, flooding lasted for days.

Storm Surge Apart from the swells that reach the coasts generated by distant storms, another phenomenon, the storm surge, is caused when strong winds blow on shore, piling up the water and causing it to be higher than predicted (Massel, R, 1999). Changes in atmospheric pressure accompanying storms can cause differences in sea level, this is called the â&#x20AC;&#x2DC;inverse barometer effectâ&#x20AC;&#x2122;. Storm surges are likely to occur along coasts with shallower waters. And when superimposed together with a spring high tide, effects can be very severe. However, in some areas the storm surges can have very disastrous effects and some not, and this is due to many different factors that influence the severity of the surge. D.Resio and J.Westerink (2008) and the National

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Oceanic and Atmospheric Administration (NOAA) point out that various processes such as: storm intensity, acceleration, wind stress, momentum transfer from wind-generated surface waves, atmospheric pressure, tidal and sea levels, and frictional drag at sea bottom and lateral mixing are all involved making heights of is primarily extreme inundation at coastal areas and may also cause severe coastal erosion, and areas in South East Asia are more at risk due to rising sea levels, and more frequent occurrence of storms.


Tracks of Tropical cyclones in 2013 Daily Positions at 00 UTC(08 HKT), the number in the symbol represents the date of the month

MAN-YI SEPAT

Intermediate 6-hourly Positions Super Typhoon Severe Typhoon Typhoon Severe Tropical Storm Tropical Storm Tropical Depression

PABUK

LEKIMA

DANAS

WIPHA YAGI JUN FRANCISCO

LEEPI TORAJI KONG-REY

SOULIK FITOW

TRAMI

SEPAT(1322) RUMBIA

USAGI

UTOR

CIMARON

TORAJI(1317)

Hong Kong

HAIYAN BEBINCA

JEBI

MAN-YI(1318) TRAMI(1312)

MANGKHUT

SOULIK(1307) YAGI(1303) PABUK(1320)

WUTIP USAGI(1319)

BEBINCA(1305)

T.D.

KONG-REY(1315)

T.D. NARI

WUTIP(1321) JEBI( 1309)

PODUL

DANAS(1324)

KROSA 1329) (

KROSA

WIPHA(1326)

CIMARON(1308) UTOR(1311) LEEPI(1304)

NARI (1325) FITOW 1323) (

FRANCISCO(1327)

Fig. 1.3.3 -2

MANGKHUT (1310) PODUL(1331)

T.D.

Typhoon Map of 2013 at the West

T.D. LEKIMA(1328)

RUMBIA(1306) SONAMU (1301) SHANSHAN (1302)

Asia).

HAIYAN(1330)

SONAMU

SHANSHAN

Waves start to slowdown and break once reaching shallow waters Coastal City

Variable Sealevel as baseline of storm surge

Low pressure at the center of the storm pulls water level up 1cm for every 1millibar change in pressure

L

Sea Level Rise

Present- 2050 = 0.08-0.12m 2050-2100 = 0.25-0.44m

2050-2100 (Floodplain) High Tide Floodplain Mean Sea Level Floodplain

Max. Tidal Range 6.75m

Low Tide Floodplain

Mean Sea Level

Fig. 1.3.3. -3 Diagram of Storm Surge (wave height exaggerated), illustrating the elevated risks of surges reaching coastal areas due to surges superposed on tides, and sea level rise.

41


1.3

HYDRODYNAMICS AT COASTS

Conclusions While most studies about waves concern the effects it causes on near-shore areas and coastlines, such as erosion, and on land such as flooding caused by surges and tides, this research on the other hand, will take into account the effects on floating villages or structures away from the shore. By grasping the fundamental principles and parameter relationship that govern wave characteristics, and appropriate factors to consider, this essentially enables the research team to carefully consider how to devise their strategies, and to identify the limitations of the project. Wave parameters and characteristics will be fundamental in designing coastal structures and strategizing for effective wave reduction. While the understanding of tides, and the influence of bathymetry, coastal morphology or basin shape will relate to site selection, and in identifying usable zones in the near-shore and offshore areas for settlements and aquaculture activity.

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1.4 RESEARCH CONTEXT Particular interest on this site is due to the scale of the of seafood and other marine products. The selected context will serve as a case study to understand and extract principles of aquaculture activity, its processes and logics, including existing settlement be selected and analyzed for testing of strategies and design applications.

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1.4.1

XIAPU COUNTY, FUJIAN CHINA

Fig. 1.4.1 - 1 Aquaculture Activities Site photos completed network that each gear has its position to support this huge sector.

Fishing Raft Village At the coast lines of Fujian Province, exists there is a man-made floating village. Most of them are found floating at inlets, and bays, and near the county, Xiapu. It is a place where local people mainly work on aquaculture industry with 53.7% people is related to aquaculture and

and the increase of consumption of seafood in China, in the area. Therefore, the unexpected issues in this area are following with the increasing number of people and the existing environment within the last decade.

and other marine products, but also a place where they live. According to research, the floating settlements in this area has been existing for 700 years, and currently almost 10,000 people live on it.

Another reason for the prosperity of aquaculture is the geographical features in the coastal line of Xiapu. However, depending on the location, generally it has become an advantage for aquaculture and has contributed to the appropriate environmental conditions

This traditional floating settlement is developed to culture livestock closely. People use cheap material that they can easily to replace and repair and light structure to adapt the environmental impact that has gradually become a severe problem recently such as typhoon. Also, due to 44

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

strategies base on the geographical features such as a landlocked lagoon, bay, and inlet shoreline to culture different species and for the purpose of adaption for environmental scenarios. ( 2001.)


China

Fujian Province

Land Area: 124,000 km2

Sea Area: 136,000 km2 (the longest coastline of China)

Land Area/ Sea Area 1.49 Km2

29.6 Km2 (within 22.2km)

= 20 time

(land area / sea area)

Population/ Fishermen = 532,000 people = 50,000 people

Fishermen

fishery output

23% Capture 52% Aquaculture

= 75% GDP (2012)

Motor fishing boats/harbors

= 53.7%

= 6,239 boats fishing harbors: 225

= 54.9%

Fig. 1.4.1 - 2

accommodate

Xiapu county information that shows the demography data of the aquatic-related population.

marsh beach shoal bay barrier island inlet sand spit

Fig. 1.4.1 - 3 Geographical feature in the Xiapu county that provide a natural aquaculture area for

longshore drift

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1.4.2

EXISTING AQUACULTURE INDUSTRY

Fig. 1.4.2-1 that float in a bay with around 2000 people live on the sea, and

Aquaculture Sector Fujian coastal area is the one of the main place that produces seafood in China. According to World Bank 2013 social assessment report, in 2011 Fujianâ&#x20AC;&#x2122;s aquatic output was 6,037,800 tons, including 5,262,035 tons of marine products, accounting for 87.15%. This is the second highest production area among all provinces in China. The prosperity of aquaculture industry has attracted thousands of people to come to invest in this culture business. And with the increase of seafood necessary in China and all over the world, the situation has been predicted will soar in following years ( . 2013) In this natural protected sea area, people mainly culture high-value market food, and they change the species by the sale price in the market every year. Currently, abalone, kelp, and sea cucumber. They are all raised 46

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

Hence, each livestock has its own culture strategies instance, the period of raising schedule is different in each species. For achieving marketing size that abalone need three years to harvest, and at least 1.5 account a daily schedule and seasonal timetable that the complexity of raising knowledge and the laborious R., & Cook, P. A. 2013) high-risk business, people still invest in it with incredible money than the inland culture business. Presently, lacking of protection for aquatic-related infrastructures and aquaculture paraphernalia are crucial problems that has happened many years. While more and more people work on aquaculture industry, the concern for the protection of aquaculture has become a mustaddress issue (Ross, L. G. 2013)


Fig. 1.4.2-2 Aquaculture Network: This diagram shows the existing aquaculture industry chain in Xiapu county.

JAN

FEB

MAR

APR

Yellow croaker fish

MAY

JUN

JUL

AUG

SEP

OCT

NOV

DEC

(1.5 years)

Abalone (3 years) Sea cucumber Kelp Gracilaria

(0.6 years) (0.6 years)

Typhoon Season

Fig. 1.4.2-2 Culture Timetable. This time schedule chart shows the prediction of culturng period for each species. It is important

(1 years)

adjust his culture process.

water temperture

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1.4.3

CONTEXTUAL CONDITIONS

Fig. 1.4.3-1 Typhoon Situation: This site suffers the strong wind and wave from the northeast. Fish cage has to against this severe climate condition annually.

Typhoon Extreme weather events have frequently hit the coast of Fujian and caused severe casualty and damages to properties and livelihoods. According to the EM_Cred database the damage losses incurred in the coastal area to several hundred million dollars in the Fujian coast for those intense typhoons recent years. The lagging and poor quality of infrastructure and disaster prevention has greatly exacerbated the property loss and personal injury and life loss during these natural disasters. Therefore, it is highly important to accelerate the construction of saving ports and shelters to reduce disaster risks and socio-economic impacts in the future disasters (EM-DAT, C. R. E. D. (2010).

extreme weather conditions. While the typhoon is coming, the only thing they can do is evacuate their homes. Although the basic protections strategies has been used for many years, such as using rope and nails to secure the rafts or by tying with another raft, and dragging the residential house to the port, the main the same place. It is because, in order to withstand the force of wave, the cages have to be anchored to the seabed when it be constructed. Furthermore, the settlement, due to the force of debris piece by wave will For this reason, a well-organized plan for locating

and their families live on the raft all year around, except

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on the sea will be a crucial issue for the design team.


Broken Fish Raft

Fig. 1.4.3-2 Damage Fish Rafts. This image circumstance of severe climate condition. Those debris not only effect environment but also affect

Existing Evacuation Strategies Simple and ineffective method

Anchor system out of function

Moving power by external force

Fig. 1.4.3-3 Local, traditional or â&#x20AC;&#x2DC;primitiveâ&#x20AC;&#x2122; strategies. It shows the strategies condition. Using basic rope methods,

rope

damaged raft

floating house

residential raft to the port.

dragging boat

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1.4.3

CONTEXTUAL CONDITIONS

Fig. 1.4.3-4

unappropriated culture environment and generate multiple effects for this area.

Unorganized Settlement in the site due to the soaring quantities of rafts. It does not only stagnate the water flow but also pollute the environment by the waste of culture species and human excreta. Recently this issue has emerged because the mass of rafts that emit all wastes into the when the number of rafts are still below the degree reach a certain numbers and waste accumulated to a certain amount that exceed the environmental

has made the ecosystem worse and adds to socioeconomic problems. Lack of management strategy hydrology condition are the main two reasons that lead to the settlement issue become a priority. Therefore, as the aquaculture industry is a main sector in the site and is getting popular than ever in the future. No doubt the quantity of aquatic output has to be increased in prediction in a case to supply the massive consumption in markets. However, on the other hand, climate issue

infected by dirty water and spread disease to another issue as the situation that has happened in this district. appropriate culture site now is depending on the experience and the death rate of species previous for the best location within a limited culture area. 50

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Mass of Fish Rafts

Fig. 1.4.3-5 High Density Settlement This image has been calculating that behind a barrier island. Although there are smaller wave and lowvelocity wind, the density of rafts has polluted this area and cause the decrease of aquatic production.

Disease Separation by Tide

high tide

>6m

low tide

Fig. 1.4.3-6 Cross-contamination. the tidal change. For this reason, the a necessary space for boat path and dampen the strength of disease.

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1.5 RESEARCH PROPOSAL This section provides the general ambitions and questions to guide the research forward in developing strategies, position experiments, and in producing the potential design output.

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1.5.1

RESEARCH AMBITIONS

Investigate on integrating strategies of wave energy reduction and aquaculture activity to develop organizational logics of floating settlements.

Aims

Research Questions

The ambition is to reduce the vulnerability and increase adaptive capacity of floating villages (existing and new) by introducing infrastructure and function programming for settlement organization. This dissertation will investigate on developing and integrating different strategies for floating settlements. The study will be contextualized in a local floating village in Xiapu, Fujian, China where current problems include - First, the lack of proper infrastructure to address the harsh environmental conditions of typhoons and large waves, and second, problems due to the informal or lack of proper organizational logic for the settlements.

Therefore, this dissertation attempts to address the following questions:

The research will explore the opportunities provided with by introducing a wave reduction system, and in considering the aquaculture activities to develop adaptive floating settlement logics. Initial strategies were informed by group discussions and some ideas synthesized from background readings. These are considered hypotheses are set in Design and Systems Ambitions (Section 1.5.2), which will be further developed or eliminated as the research progressed.

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1. What type of infrastructure can be introduced for wave energy reduction system that is also adaptable to floating settlements? 2. How can the limits of scale and pattern of the wave reduction system influence the development of floating settlement organization logic? influence the settlement organization logics for floating villages?


lem and solution

Effect of Typhoon to floating settlement

Local peopleâ&#x20AC;&#x2122;s heirachy of importance

1

2

3

4

Life

Fishing boat

Aquaculture

Habitat

RISKS

CAUSES Non-existent strategies

Unorganized Settlement planning

Insufficient boat berthing 54% lacking places

Evacuation plan

Anchor points

Lost and Damage - Anchor points - Aggregation - Wave breaker

Program

Infrastructure

+

INTEGRATED STRATEGIES

Fishing boat

Aquaculture

Life

Habitat

Wave Reduction

Settlement Organization

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1.5.2

DESIGN AND SYSTEM AMBITIONS Anchor points Anchor points that the system provide strength to the overall floating unit clusters by providing the localized anchor points related to the incoming wave energy and directions. These nodes may function as the distribution of local ports serving the lacked facilities reducing the lost of

Strengthen community Settlement pattern The variable risk and intensities of wave attenuation in each location then indicates the typology and amount of anchor points. The different degree of wave energy also indicates zoning for settlements program.

1

2

3

4

Public Facility

Private

Wave attenuation The outer edge clusters towards the ocean then form the defense for the inner clusters forming the variable local wave conditions occurring in the negative space between clusters. The wave energy is minimized or redirected.

1

2

3

4

Wave energy

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Aquaculture

Aquaculture logic From the integration of anchor system and settlement cluster emerges the wave attenuation system, which reduces the risk of aquaculture farm loss during typhoon. The optimization between aquaculture and required wave conditions and results condition among the clusters form the aquaculture and settlement network.

Connection to land Connection of Land and Ocean Evacuation plan and aquaculture industry requires optimized planning of connectivity between land and ocean. The optimized logic between both wave attenuation and settlement logic can emerge from wave attenuation patterns

Underwater Contour

Underwater contour

Network of submerged anchor systems forming the porous morphologies encourages marine biology revitalization.

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2.0 METHODS


2.1

PROCESS

RESEARCH STAGES

(

RESEARCH PROPOSAL

)

Data Analysis

RESEARCH AND COMPUTATIONAL PROCESS

(

RESEARCH DEVELOPMENT

Abstraction

Precedents

Parameters, Parameter

Site Information

Equations Boundary Conditions

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)


(

DESIGN DEVELOPMENT

Inputs

)

(

DERIVED DESIGN SCENARIOS

Computational Tools Experiments

Generative Tools

Design Strategies

Evaluative Tools

)

Output Solution Sets

Feedback Loop Fig. 2.1 -1 Process and Tools Chart Diagram illustrating the research stages and computational process and how each tool or technique in general is applied in the research.

Process Overview Based on the aims to reduce wave energy and explore potential for settlement organization logics, various digital tools were explored and tested to facilitate the design strategies. This also influenced the boundaries or limitations of the research. However, techniques such as conducting case studies, literature review, and scripting algorithms based on established models or research, provided an alternative approach to computational process includes the use of software, and scripting algorithms. The above diagram shows the initial strategies and which tools are utilized for its development.

2.0

METHODS

61


2.2

TOOLS AND TECHNIQUES

Linear Algebra-Matrix Calculation and Binary Search In a traditional way, search or changing the items inside the list will need to iterate through the whole list till always deals with large amount of individuals ranging from several hundreds to several thousands. Iterating through the whole list will not be a good strategy. Several algorithms have been used to speed up the calculation speed. In order to search for a proper value within a ranked list, therefore, binary search has been used. By applying the binary search method, the iteration times has been reduced from around 700 to below 30 to get the proper result. For representing two-dimension list of values, mathematics library named NumPy and SciPy are used. Two-dimension matrix can easily meet the requirement.

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Matrix calculation will be much faster when dealing with the relation between several 2D lists. In algorithm that generating platform mophorlogy, Cellular Automata is with NumPy library.


Cellular Automata

CFD and Wave Analysis

Cellular automata(CA) is a computational model that uses discrete method to solve mathematics, physics, complexity science, biology and micro-structure modeling (Wolfram,1983). Based on its properties, it can help to solve lots of the bottom-up procedure.

The implementation of CFD techniques in

CA illustrates the state with time axis, it can provide a simple two dimension pattern with one dimension state. With proper rules set- up, a three dimensional pattern will be generated by the two dimension start state. CA together with genetic algorithm has been used in the wave reduction unit design to generate platform structure that follows a bottom-up procedure.

this

tools such as AutodeskSimlation CFD, Flow3D to get the result in material scale. During second stage, the principle and logic of CFD method has been carefully studied. Code in Python was written using LBM(Lattice Boltzmann Method) for testing simple CFD process in a particle scale. At last stage, the CFD principles are that can operate in a much larger scale with the help of published physical CFD experiment results. Algorithm has been written in python, then optimized and written calculation speed.

2.0

METHODS

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2.2

TOOLS AND TECHNIQUES

FEA Structure Analysis FEA Analysis has been widely used in structure evaluation software. There are large amount of software providing structure analysis in different levels of resolution. For this research, only relative results are required, and FEA results the research and design. The advantage of using Karamba is it generates realtime evaluation results within most of the modern programming environment. It currently supports JAVA, Pyhon, C# environment and the Grashopper Design scripting environment in Rhino3d software. The rigidity of the public platform will be evaluated using Karamba. By integrating it with the morphology generating logic, we will be able to use it with GA for individual selection.

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Multi-Objective Optimization (Using GA) For a nontrival muti-objective optimization problem, it is inappropriate to provide a single solution that optimized the objectives at same time, the objective functions are said to be conflicting, in this case, non-dominated solution should be provide as the optimal-results. All Pareto optimal solutions are considered equally â&#x20AC;&#x2DC;goodâ&#x20AC;&#x2DC; for the muti-objective optimization. With the selection, crossover and mutation procedure of genetic algorithm, every generation of optimal-results will inherit the proper genome from previous generation but keep diversity. software Rhinoceros, we build the nodes and edges in C#, then convert them into topological verticies and edges after optimized . Topological diagram has been convert into a more readable depth diagram by the algorithm written in python. (See Appendix)


Graph Data Structure Graph is widely used in computer science to organize and represent data structure. It consist of nodes and edges to illustrate the identity of node and relation between nodes. Urban networks can be abstracted and described in graph structure. The converted topological relation of the urban networks can be calculated and

software Rhinoceros, we build the nodes and edges in C#, then convert them into topological verticies and edges after optimized . Topological diagram has been convert into a more readable depth diagram by the algorithm written in python.(See Appendix)

two nodes and centrality of each node and the shortest path in this research. Being widely used by computer science and other the set up procedure and provide algorithms used for network calculation. NetworkX for Python and QuickGraph for C# has been explored and used in this research, details will be mentioned later. 2.0

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3.0 RESEARCH DEVELOPMENT Testing of abstracted principles and and parameters methods and strategies for design

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3.1 ANALYSIS 3.1.1 Principles and Parameters Part of the research was to investigate on systems that offer wave attenuation performance. Two categories were studied: First, by looking at natureâ&#x20AC;&#x2122;s coastal biological systems, and second, by studying manmade coastal structures. The aim of studying these precedents was to abstract principles and parameters related to wave energy reduction and re-direction. The following sections discusses the observations and reviewing and comparing related literature, articles and published experiments. It highlights their observations of the important parameters, considerations, advantages and disadvantages of the systems, and potential for design application. Understanding how the underlying principles of the existing wave attenuation systems work in relation to the physics of waves was vital to the development of the research proposal as well as the setting of strategies and experiments that ensued.

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3.1.1.1

COASTAL BIOLOGICAL SYSTEMS

Nature provides coastal protection through its coastal biological systems, and these are developed over a

Fig. 3.1.1.1-1 Waves break over a coral reef off the coast of Mahe, reducing wave before it reaches the coast. Image Source: ocean.nationalgeogrphic.com Photograph by Roberto Schmidt AFP/GETTY IMAGES

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the amount of plant and sedentary animal material obstructing the water column and bathymetry (underwater topography) provides the wave attenuation function of these systems. Friction is achieved through various sources, such as the reticulated structure of the coral reef, and the leaves, stems and roots of mangrove trees and grasses. These affect the momentum of the water and results in the reduction of current velocity and attenuation of wave energy.

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Through Biomimetics, this dissertation investigates three biological systems: the coral reefs, mangrove forests, and salt-marshes. Through the investigation, it was realized that these systems function differently when observed in a small scale to a large scale. Each of these coastal biological systems is composed of many different types of species, and often vary in their morphologies. Their growth, location and position in relation to the seaward side and land, contribute to the overall geometry of the system to help attenuate waves.


Fig. 3.1.1.1-2 Orbicella annularis or ‘Boulder Star Coral’. Can grow to different morphologies based on varying light conditions. Image Source: http://flowergarden.noaa.gov Genus Acropora. Considered fastest growing coral type. Depending on the species and location , it can grow either slender, think or flatplate branches (Staghorn, Elkhorn, orTable Coral). Often found in shallow reefs, with good sunlight penetration and moderate to high water flows Image Source: http://www.noaanews.noaa.gov Acropora Palmata Frank O’Donnell www.inkbox.net Acropora Cervicornis ww.fau.edu

Rahman. Licensed under CC BYSA 4.0 via Commons - https:// commons.wikimedia.org/

Corals and Coral Reef Corals are small organisms called polyps with soft tissues that deposit calcium carbonate when it attaches to a surface of a rock or sea floor. These polyps clone creating a colony that acts as a single organism. These colonies then join together to become reefs, and this process takes over hundreds and thousands of years. The morphology of the corals and the reefs and how these contribute to wave energy reduction are the point of interest for the dissertation team. Two scales are morphology of one colony or coral type, and the global scale - the shape of the reef types.

Coral Morphology Corals have many types of morphologies (Fig. 3.1.1.12 )and studies have shown that the variation of morphologies have emerged from the colony’s response

to its environmental conditions, particularly light and hydrodynamic energy, but may also depend on the organism’s strategy for growth and reproduction. In the study by Chindapol et.al (2013), the coral Pocillopora Damicornis is said to grow towards the direction of the flow of water to capture the most nutrients, or generate micro-turbulence for nutrition distribution or waste removal. For the coral Acropora Cervicornis, it grows slim branches that are brittle, that tend to break in rapid water flow, but this coral thrives in turbulent and wave-swept areas. Koehl, M.A.R advantageous for organisms that can regrow, and to reduce the amount of water flow stress to the structure. However, little is suggested on how these coral morphologies help in attenuating wave energy when observed at a colony scale, but the resulting morphology responses to the environment concerns more on the 3.0

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a) Oxygen,Nutrition

Water fluid

Waste

Fig. 3.1.1.1-3 Diagram illustrating the Function of Coral Morphology - based on genus Acropora (Left) a) Using its branch structure to control circulation inside the colony b) Interseting feature is the breaking of the branch to facilitate the reduction of forces implied on the structure Reference: Koehl, M.A.R (1984)

b)

â&#x20AC;&#x2DC;survivalâ&#x20AC;&#x2122; of the structure of the organism itself.

Reef Morphology Looking in a larger scale, the various coral colonies aggregate to form a reef. Three main types of reefs include: Fringing Reefs - typically found in shallow waters, and grows from the coasts; Barrier Reefs grows further out from land, and separated from land ba a stretch of water; and Atoll - a reef that surrounds a deep lagoon or volcano. The overall reef morphology provides the underwater to the incoming waves, it is able to attenuate wave energy. This causes waves to already break while far from the shore, reducing its energy before reaching the beach land. Ferrario et.al (2013) reports that the coral reef attenuates wave energy at the reef crest by 84%, 72

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reef flat by about 50% more. by the time it reaches the shore, 97% of the wave energy has been dissipated. (Fig.3.1.1.1-4. Also, in the similar study, they report that the perfromance of the whole reef in reducing wave energy shows are linear from small waves to hurricane

account that due to the rapid changes in the envrionment brought about by climate change, and wave attenuation is important to identify the principles that would make it reduction systesms. These include: Shape of the Reef, Depth of the Reef, and appropriate size or scale of the reef, and its distance from the coastline to the edge of the reef.


WHOLE REEF

REEF FLAT

FORE REEF

REEF CREST

shallowest part of the reef, and

reduced water circulation, theaccumulation of sediments and periods of tidal emersion.

150 m

WAVE ENERGY

WAVE ATTENUATION 97 %

100 % 5.5 %

3%

14 %

Typhoon and Cyclone wave ( 7-13 m. height )

WAVE HEIGHT

100 % 26 %

16 %

36%

0

-2 FRICTION

100

100

90

90

80

80

70

70

Wave Attenuation (%)

Wave Attenuation (%)

Depth (m)

60 50 40 30 20

0

60 50 40 30 20

10

Fig.3.1.1.1-5 Graphs illustrating the amount of wave reduction at the reef crest area, and how much more is reduced at the reef flat zone. Most of the energy is attenuated within 1000m of the reef flat (Graph A). The whole reef functions to reduce wave energy to almost 100%.

10

0

2000 3000 1000 Reef flat width (m)

4000

-5

Fig. 3.1.1.1-4 This diagram illusrtates the areas of the coral reef. Wave attenuation happens majority at the Reef Crest, because of its global geometry where water depth suddenly becomes shallow - a critical factor affecting wave characteristics. References: Ferrario et.al (2014), www.newsmongabay.com

0

Reef crest

Reef flat

Whole Reef

Part of Reef Wave Energy Wave Height

Adapted from Ferrario et.al (2014), www.nature.com

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3.1.1.1

COASTAL BIOLOGICAL SYSTEMS

Fig.3.1.1.1-6 Mangrove Forest at the Atlantic Coast http://www.isciencetimes.com/

Mangroves and Mangrove Forests Mangrove forests are commonly located in tropical and sub-tropical regions, along coastal areas and estuaries. Mangrove trees grow on alluvial plains, where soils are submerged by rising tides. The mangroveâ&#x20AC;&#x2122;s dense, tangled roots slow down the water flow velocity and facilitates sedimentation trapping, therefore reducing coastal erosion and innundation depth. These forests are widely studied to because of its ability to attenuate wave energy and provide coastal protection. Many studies have been made on mangrove forests attenuating tidal flows and wind induced waves, but Latief and Hadi (2007) however argues that some of the studies mentioned earlier provide important information related to attenuating wave energy, but cannot be directly applied in the case of tsunamis. They note that tsunamis are transient waves with longer wavelengths and have larger impacts on coastal areas. 74

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Koch et.al (2009) reports the study by Shuto (1987) suggests that 20-100m wide mangrove belt would be necessary to protect against tsunami waves of 3-6m in height. Also, they report Mazda et.al (1997) predicted that mangrove forest as wide as 1000m might be required to reduce wave energy by 90%. However, the effectiveness to protect against tsunami will be be dependent on tree density rather than the spatial extent of trees. Density is also a factor correlated with the age and species of the mangrove trees. Very dense mangrove forests full attenuation of wind induced waves may occur within 30m of the edge, while in low density mangroves such as those usually found at the edge of mangrove forests require a wider vegetated area to obtain same results. This immediately give the researchers insight on the critical parameters to consider in making wave attenuation effective for mangroves: First, plant material density, and secondly, the width and depth of the forest.


500-1000+m wide Mangrove Belt

SEAWARD ZONE

30-250m WAVE ATTENUATION 86-90%

But varies according to density of the forest

WAVE ENERGY(E) 100 %

75%*

25%

10-14%

20-100m wide Mangrove Belt

Ceriops Species

Aegiceras Species

Tsunami (3-6m Ht.)

Wave Direction

Rhizophora Species

High Tide H = 1.80m

Fig.3.1.1.1-7 Illustation with Graph showing Wave energy reduction and percentage of wave attenuation by Mangrove forest based from the various studies reported in Koch et.al (2009)

Fig.3.1.1.1-8 a)Mangrove roots showing the dense tangle of prop roots, allowing the trees to handle the daily rise and fall of tides, and help stabilize coastline. b) Sea grasses

For the Mangroves, it is performing collectively in two balance of both density of the tree roots and stems, and spatial coverage or extent of the forest. But then may also depend on the wave situation, such as the wave length, wave height and period.

Salt Marshes and Sea Grass

study by Koch et.al (2009), it can be concluded that the effectivity of these grasses to achieve wave attenuation is observable in a larger scale. They report that sea grass (Rupppia maritime) in early growing season shows little contribution to wave attenuation. It nees to reach a threshold of 1000 shoots m2 before this ecosystem function (wave attenuation) is observed. In the similar effectiveness of sea grass and salt marsh grasses . Figure 3.1.1.1 -11 show that as water depth increases the amount of wave attenuation is less than 10%.

Other plant material are also found in Tidal flats such as grasses. On different species are found in different layers or zones depending on their location from the seaward zone to inland areas. They vary in thickness of grass blades to sensitivity to salt water. However, the

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COASTAL BIOLOGICAL SYSTEMS

Salicornia Marsh

Spartina Alterniflora

Tidal Flat

Sea Grass

Potentially non-reducing or rebuilding wave energy

Density of 2 1000 shoots /m before it provides protection

High Tide

WAVE ATTENUATION 99%

WAVE ENERGY 100 %

90%

30% 1%

Low Tide

WAVE ATTENUATION 99%

WAVE ENERGY 100 %

70%

60% 1%

Wave Direction High Tide

Fig.3.1.1.1-9

Depth (m)

Illustation with Graph showing Wave energy reduction and percentage of wave attenuation of salt marsh ecosystem. (Koch et.al ,2009)

Low Tide

-1.2m

Fig.3.1.1.1-10

1.0

b) Graph illustrating the effectiveness of marsh, mangrove and seagrass in wave attenuation dependent on water depth Refereces: Koch et. al,( 2009)

2.0

0.8

1.5

0.6

1.0

0.4

0.5

0.2

0.0

0

50

100

150

200

250

80

0.0 300

Distance from marsh/Mangrove edge (m)

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Mangrove wave attenuation (m-1)

a) Graph showing the amount of wave attenuation achieved as water moves from the seaward side to within the system

Marsh Mangrove

Mangrove wave attenuation (%)

Fig.3.1.1.1-11

Marsh wave attenuation (% m â&#x20AC;&#x201C;1)

2.5

Marsh Mangrove Seagrass

0.006

60

0.004

40

0.002

0.000 0.0

20

0.3

0.6 Water Depth (m)

0.9

0 1.2

Marsh, seagrass wave attenuation (%)

Salt marsh grasses a) Salicornia marsh. b) shows two salt-marsh species Spartina Alterniflora (right of image), usually found in low marsh, beside open water and is flooded twice a day by tides; and Spartina Patens species.


Wave Energy Reduction through density and generating turbule

Spacing

Select Functions

Biology Coastal Biological Systems that offer wave energy attenuation service

Performance of Biological System through Morphology

DENSITY: No. of Units, Pattern Spacing over given area

Depth

Abstraction Spacing

POROSITY:

DENSITY: Amount of Surface Area in DENSITY: DENSITY: No.Units, of Units, Pattern Spacing contact with water over a given No. of Pattern Spacing volume No.DENSITY: of Units, Pattern Spacing over over givengiven areaarea Mangrove Roots , Mangrove Forest Wave enrergy distribution / reduction over given area No. of Units, Pattern Spacing over given area

Length

Length

Velocity Reduction

Porosity

Velocity Reduction

Friction, Turbulence, Surface Pressure

Wave Energy Reduction through density and generating turbu

Spacing

Depth

Length

Width/ No.of Rows

Micro-current/ Turbulence Generation

Turbulence, Friction,Friction, Turbulence, Surface Surface PressurePressure VelocityPressure Reduction Friction, Turbulence, Surface

Density

Friction, Turbulence, Surface Pressure

Friction, Turbulence, Surface Pressure

over given area

GROWTH & AGGREGATION GROWTH & AGGREGATION Morphology based on response Morphology based on response to to flows (hydrodynamics) flows (hydrodynamics) GROWTH & AGGREGATION GROWTH & AGGREGATION POROSITY: Morphology based onon response toto Morphology based response Salt Marsh, Sea Grass Amount of Surface Area in flows (hydrodynamics) flows (hydrodynamics) contact with water over a given Growth responsive to flows to lessen

Conclusions

Length

Length Velocity Reduction Velocity Reduction

Width/ No.of Rows

GROWTH & AGGREGATION Morphology based on response to flows (hydrodynamics)

volume

Depth

Depth Width/ Width/No.of Rows Width/ No.of Rows No.of Rows

POROSITY: POROSITY: Amount of Surface Amount of Surface AreaArea in in POROSITY: contact water a given contact withwith water over over a given POROSITY: Amount of Surface Area in volume volume Corals, Coral Reef Amount ofwater Surface Area in contact with over a given contact with water overDENSITY: a given volume volume No. of Units, Pattern Spacing

SpacingSpacing

Functions achieved through principles, Length Width/ No.of Rows and governing parameters. To be Spacing investigated and applied to develop Velocity Reduction Depth system ambition Depth

Wa Wave Energ through den through density and g Wa through den

surface pressure on structure

GROWTH & AGGREGATION Morphology based on response to flows (hydrodynamics)

Although coastal biological systems provide wave attenuation service, their effectivity is dependent on a lot of factors, therefore they are considered non-linear and do not provide a consistent wave attenuation service. (Koch.et al, 2009). There is also a risk of it being destroyed during exteme weather events where they are needed most. Also they face other vulnerabilities such as harmful human activities. These systems are still an important part of the coastal ecosystem, and needs to be preserved and managed properly. If these systems are available at a site to be developed, it must be considered there to complement, not provide the full wave attenuation service. After a careful study of these systems, it is learned that the coral reef functions primarily as the wave attenuation system breaking the waves and reducing wave energy by upto 97% before reaching the shore. The other systems such as the mangrove forests and salt-marshes function more effectively in preventing the

Fig.3.1.1.1-12 Biomimetic Abstraction of principles taken from the study of different coastal biological systems, viewed Turbulence, Friction,Friction, Turbulence, Surface Surface PressurePressure at different scales

Friction, Turbulence, Surface Pressure Growth and Aggregation

Friction, Turbulence, Surface Pressure

Friction, Turbulence, Surface Pressure fast flow of water inland, reducing the risk of flooding when tides rise. Also, in obstructing and slowing down water flow velocity of storm surges approaching the shore. Nevertheless, these systems have functions in Friction, Turbulence, Surface Pressure common. The morphology either from local to global scales are primarily used to obstruct or create friction on the wave structure. Submergence or the depth of these systems in relation to the wave structure is one critical location and width of the system, how far from the shoreline, and how much it

three other principles that govern these systems which are deemed essential to this dissertaion either on design systems: Porosity - amount of surface area in contact with the water in relation to the given volume; Density - the number of units in a given area; and its strategic Growth and Aggregation - in attempt to reduce effects of forces on the structure To test these principles, basic experiments were carried out to further understand the governing parameters and are presented in Section 3.2.

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3.1.1.2

MAN-MADE COASTAL STRUCTURES

The study also investigates man-made coastal systems potential as breakwater, while also touching briefly on principles of mooring systems. Breakwaters are fundamentally used to attenuate wave energy, reducing wave transmission to protect and manage the coast. In

By using literature review of published research, books and Internet sources, the aim is to have a direct and concise understanding the principles and logic behind the geometry, design, and fabrication and materials used. This section briefly discusses parameter relationships and limits of application. Parts of the study are done parallel while testing its principles, equations through experiments and applications to an algorithm, and proposed strategies.

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Above: Underside view of an off-shore processing facility, with chains as mooring lines. Photo taken from:www.upstreamonline.com

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MAN-MADE COASTAL STRUCTURES

Fig.3.1.1.2 -1 Floating Breakwater Image taken from www.nauticexpo.com

Floating Breakwater

80

There are many different types of floating breakwater, each varying in design and performance in attenuating wave energy. For this dissertation, the aim is to understand the principles and parameters of more common breakwater types that are considered easier to analyze and have been previously studied. This will serve as a foundational basis for the wave reduction system design.

3. It presents minimum interference with water

et.al (2008) suggests the system should be inexpensive, convenient to operate, and effective. The following are some relevant characteristics or advantages of using floating breakwater (FB) presented by Dong et.al (2008) based from their study of McCartneyâ&#x20AC;&#x2122;s (1985) characteristics: 1. Floating Breakwaters may be the only solution for poor foundations or soil conditions 2. They can be much cheaper than bottom founded breakwaters in depths greater than 6m

Given these characteristics, the research team views Floating breakwater as an appropriate precedent towards their design ambition, as opposed to rubble mound breakwaters or bottom founded breakwaters for the reasons of flexibility, potential applications in deeper water, and less use of material, disturbance or obstruction of water flow at the sea floor.

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submerged rubble-mound breakwaters. a minimum visual intrusion on the horizontal plane, in particular for areas with high tidal ranges. 5. They can also be rearranged into a new layout with minimum effort.


Attenuate or reduce waves

support weight of

wave induced hogging and

moorings consider mooring forces during storm

(standard practices of

Fig.3.1.1.2 -2 Table of Four Fundamental Breakwater design considerations

Catamaran

Twin Catamaran

PONTOON RAFT

BOX PONTOON

RAFT

1

Fig.3.1.1.2 -3 Illustation with Graph showing Wave

0.8

main types of floating breakwater. 0.6

Cheng et.al (2013) study of Hales (1981).

Kt 0.4 0.2 0 0

0.1

0.2

0.3

0.4 W/L

0.5

0.6

0.7

0.8

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3.1.1.2

MAN-MADE COASTAL STRUCTURES W

Ht

FB

d

Hi Incident Wave Height

Transmitted Wave Height

h

Parameters

LCL Anchor Sea Bed

Parameters

Fig.3.1.1.2 -4

FB W Hi Incident wave height Ht Transmitted wave height d

Basic Components and Parameters of a Floating Breakwater

h LCL

+W

+d

Parameters & Relationships According to the studies, the width of the breakwater effectiveness of the breakwater to decrease the wave according to the wave conditions of the context. (Dong , G.H., et.al 2008; Pena, E. et.al, 2011, L.H. Cheng, et.al, 2013, Elchahal, G. et.al, 2009). However, wave conditions that occur in nature are inherently non-linear due to many factors affecting its characteristics and behavior. Therefore a the width must be adaptive, or designed for the most extreme condition in the context. The effectiveness of the floating breakwater relies on the ratio of its width to the wavelength of incoming waves. Also, an increase in the width in relation to the depth of the breakwater determines its rigidity or further increase in weight. A long width with non proportionate depth will make the system ineffective in wave reduction as shown in the studies of Dong,G.H. et.al, (2008). According to 82

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Elchalal G. et.al (2009), the breakwater width in relation to the submerged portion of breakwater (draft), and its influence on the increase of weight of the brewakwater affects wave transmission. The heavier the structure, the harder for it to be put into oscillation. Wave and Breakwater Parameter Relationships indicating the effectiveness of the breakwater in effective the breakwater. In the study by L.H. Cheng, et.al (2013), it shows that the relationship of H/L (wave height and wave length) at the condition it reaches a breakwater unit depth over wavelength) comes into effect


Combined Ht

Ht2

Ht

W

Separate W

2Wr

Ht1

Hi

W

Hi

Hi Fig.3.1.1.2 -5

Wr =W/L

Wr =W/L Ht

Ht1 Ht2

r

Wave Transmission has same result either two units are combined or separate.

r r

1

Ht = Ht 2

r

r

n

r

0.8

r

0.6 Kt

K

0.4 0.2 0 0

experiment, it is observed that the relationship of the dependent on the scale of the breakwater (i.e. the setup of the experiment). Such relationship shown in the graphs are only applicable to the bounds conditions of the experiments caried out by L.H. Cheng, et.al (2013) which are of wave periods less than 4s, and width of the breakwater is less than 10 m) contrary to the projectâ&#x20AC;&#x2122;s ambition of addressing periods in between 6-15s.

0.2

0.3 W/L

0.4

0.5

0.6

1 0.8 0.6 Kt

While applying the relationships of W/L presented in the graphs by L.H.Cheng, (2013) to the design experiments, the wave height is reduced by increasing the (W) by multiple units. The behavior is similar whether units are combined or separate.

0.1

0.6

0.4

Fig.3.1.1.2 -6

0.2

Illustation with Graph showing Wave energy reduction and percentage of wave attenuation. Adapted from

0 0

0.2

0.4

0.6 D/L

0.8

3.0

1.0

1.2

(2008)study.

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3.1.1.2

MAN-MADE COASTAL STRUCTURES

FB

Catenary - Chain Type

FB

FB

Fig.3.1.1.2 -7 Different Types of Mooring systems for floating breakwaters. Drawn based on descriptions from E.Pena et.al (2011)

Sea Bed

Rigid - Pile Type / Taut Type

Elastic Type

Floating Breakwater Mooring System Determining the mooring forces is an essential part of floating breakwater design. The effectiveness of the floating breakwater’s performance in wave attenuation is also the outcome of the mooring system’s performance in maintaining its position during extreme weather conditions such as storms. Headland, J.R.(1995) states that the characteristics of a mooring system has a direct relation to the wave transmission performance and structural design of breakwater. In his study, two types of mooring systems were presented that are common for floating breakwaters. These are the Guide Pile and the Catenary mooring systems. Headland, J.R. (1995) reports the mooring forces obtained from hydraulic model testing by Davidson (1971), that the guide pile system receives 10 times greater mooring forces compared to the catenary system. (Fig.3.1.1.2-8). Catenary systems on the other hand, by use of chains suspended from the breakwater to the sea floor have more range of motion, and are ‘softer’ guide pile 84

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systems, resulting in lower mooring forces, but does not waves. The catenary type systems though offers more cost advantage to guide pile systems when considering water depths of more than 10 meters. In another study, a comparison was done by Pena et al. (2011) on elastomeric lines and chains as components of the mooring system. Their aim was to extract the testing a rigid mooring system as the pile type, results show that impact type forces peak at 20 tons with a rigid mooring system. By introducing an elastic mooring system, the load was reduced to 40% maximum. They have also observed a dampening of forces and more homegenous distribution of loads to different mooring lines. However, for small wave heights and wave periods, greater force values were recorded for the elastic mooring lines, since these


1200

5000

4000

Anchor Force (F) per foot

Anchor Force (F) per foot

1000

800

600

400

2000

1000

200 0

3000

0 0

1

3

5

Incident Wave Height, ft

0

1

3

Incident Wave Height, ft Fig.3.1.1.2 -8 Catenary Moored Floating Breakwater and Pile Moored Floating Breakwater. Adapted from Headland, 1995, based on Davidson 1971)

are pretensioned and restrict the orbital motions of the breakwater in these conditions.

Another study by Elchahal et.al (2009), investigates the effect of the angle of inclination of mooring lines. They

Also, they found that rigid and elastic mooring lines typology have no influence on wave transmission as

effect to limit the oscillating, motions of a breakwater in the presence of incoming waves. Stiffness of the mooring lines also affect the stability and amount of vibration of the breakwater structure. By increasing the stiffness, it limits the motion of the breakwater. However, the mooring line stiffness can be compensated by having larger structures, which limits the amplitude of the breakwater movment due to larger hydrodynamic damping. Also in the same study, Elchahal et.al (2009) reports that the motions of the breakwater sometimes help in wave attenuation because of its position against incoming waves.

values when tested with each type. This result may be brought about by the boundary conditions it was tested with. On the contrary, J.R. Headland (1995), argues that wave transmission performance still depends on the and mooring properties. Also he suggests that mooring systems are to be considered or developed separately in design, but has to work with the breakwater design iteratively, because breakwater design influences the effects on the mooring systems by reducing the overall forces that are transmitted or dealt with the system.

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MAN-MADE COASTAL STRUCTURES

heave

with initiating forces

z

x

surge

z

pitch

x

Fig.3.1.1.2 -9 Different motions of the breakwater in response to incoming waves

Floating Breakwater Motions and Structure Critical Condition Similar to a ship, the floating breakwater (single unit) is subject to various motions and will greatly affect the stability of the system. The prevalent motions of a breakwater are heave- the vertical movement, sway - forward and backward movement of the breakwater in direction of the wave, and roll - the rotation along the length of the breakwater. As mentioned in the previous page, it is influenced by the stiffness and angle of inclination of mooring lines, and the mass of the breakwater. The motions may also aid in reducing transmission as reported by Rahman and Womera (2010) and Elchahal et.al (2009) as illustrated in Fig.3.1.1.2 -9 .However, the motionâ&#x20AC;&#x2122;s effective to reduce waves is also dependent on wave characteristics such as wavelength, period and wave height. Therefore it does not always help in wave reduction, since it relies on many factors and conditions for it to be effective.

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Roll Motion

dampen the waves


When units are aggregated, they function collectively as one unit. However, the connection between two units becomes critical as these absorb the forces subjected to it. The connection must be strong enough and have whole system serve as a damper for waves with very high periods. To minimize shear stress in the module connectors, Pena, et al, (2011) recommends that all breakwater modules should be anchored to the bottom of the sea. Elastic mooring lines improve load distribution among different anchors and produce a damping of the impact loads.

Fig.3.1.1.2 -10 Structural Critical Condition, when floating breakwaters encounter oblique waves or if wavelength is equal to the width of the breakwater. Connection points become an issue.

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3.1.1.2

MAN-MADE COASTAL STRUCTURES

Fig.3.1.1.2 -11 ter to control beach erosion

to help revitalise, regenerate degraded marine habitat, new marine species to a particular area. This is done so by mimicking characteristics of a natural reef. Different methods and materials are used to construct platforms and other offshore structures may function wood and PVC were previously used, and more recent developments by companies and foundations have found the use of limestone, steel and concrete to manufacture longer-lasting and environmentally friendly Norris, 1989, www.reefball.org). Apart from marine habitat regeneration, other developments and research

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be used as a submerged breakwater. Functioning similar to a natural reef, when placed offshore, it helps in wave refraction and attenuation, to control beach erosion, stabilize shorlines and improve beach nourishment projects (Harris, 2009). Study by Armono (2004) suggest changing the mindset of coastal engineering from a ‘hard’ to ‘soft’ structure approach. Based on the data gathered by the dissertation team comparison (Fig.3.1.1.2 -12) aim to identify what key parameters should be considered for the ambitions of the project, and as precedents for developing a material system design. The focus of the project will not be on revitalizing marine life, but to identify the principles and parameters behind the potential of the system to reduce wave energy.


Reef Systems

Concrete Pipes

Concrete Blocks

Reef Ball

Struture (MARS)

Unit

Aggregated Units

CRITERIA

Geometry Component’s scalability, space

0.45-1.5m dia. upto 3.7m length 120-400kg

1.0x2.0m

25-2727kg 0.46-1.0m Ht 0.3-2.0m Width

1.2x1.2m 1150kg

especially at larger scales

30kg units Designed in parts, assembled to form one unit

Aggregation The component’s capability to aggregate potentially in different planes and cover larger area

60 pipes = 1200m2 Stacked and tied together. Aggregating method loses potential of Cylindircal geometry

Stacked and tied together.

Effective depth of placement (for coastal protection is imited to the largest available unit size

Joint and Clip System Large scale aggregation (Untested) Might be harder to replace parts when damaged

Materials Suitable for coral growth, not altering ocean pH level, durability

Concrete

Concrete/Steel

Concrete

Ceramic Outer layer Concrete internal structure with steel rod for reinforcement

Function System’s potential use other than marine ecology revitalization i.e. Stability for coastal protection

Damaged Concrete Pipes. Very unstable Rolls and crushes benthic organisms Poor dispersion

Structurally stable, suitable for reef regeneration, has good dispersion rating

Widely used, developed and researched since 1993, used for coral regeneration and coastal erosion protection

Bulk Volume (m3)

Currently used for corals and marine life regeneration

Assessment Legend***

Dispersion =

Most Effective

Area Covered (m ) x Water Depth (m) 2

Fundamental System Properties

Geometry, Material Type, and Method of Aggregation or placement, these are key to the system’s effectiveness in revitalizing marine life, and in potentially serving as wave reduction system. founded, or placed at the sea floor. It needs to be stable and remain in place to resist hydrodynamic forces. This is often achieved with a large amount of mass and density per unit, such as the ‘Goliath’ ReefBall unit reaching approximately 3000 kilograms. This however requires heavy equipment and expertise for installation.

total assembled weight of one unit is just 30kgs. Divers can shift and assemble them with ease at the seafloor. This method of MARS has been effective for dispersion, however, its limitation for aggregation and potential for wave reduction performance has not been studied yet. Stability performance is a result of the three basic properties. Units can either be scaled in size, use a more dense material, or aggregate multiple units together to increase mass. When sea floor conditions are too soft, some systems inject steel rods as anchors.

Least Effective

Fig.3.1.1.2 -12 Comparative Assessment 4-Types of Floating Breakwater. References: www.reefball.org; www. reefdesignlab.com; R.Brock & J.Norris (1989); pp.10-12 D.S. Amouil, (2008)

Reef System (MARS), emphasize on the handling and deployability of the units by designing them in parts, and

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of


3.1.1.2

MAN-MADE COASTAL STRUCTURES Wave Direction Onshore

Ht

Hi

Offshore SWL High Tide SWL

F

SWL Low Tide

B

d h

Fig.3.1.1.2 -13 Fundamental Parameters of Submerged breakwaters.

Effectiveness of Breakwater: Relative structure height h d

; 0.6 -0.8

Degree of Submergence d h

< is better

<K

t

=

Hi Ht

F

freeboard

SWL Hi Ht B h d

Still water Level Incident wave height Transmitted wave height Crest Width height of structure depth at toe of structure

Parameters and Limitations for Wave Reduction

wave reduction performance. Its characteristics of mimicking a coral reef presents an opportunity, but current designs provides a critical limitation. Armono, H.D., (2004) highlights that the Wave Transmission

The location and placement of breakwaters also influences the amount of wave reduction and current generation. Although, the study for current patterns are widely focused on the effects of sedimentation and beach erosion, this can be a potential for controlling or generating micro currents for aquaculture.

breakwaterâ&#x20AC;&#x2122;s effectiveness, and this is achieved through varied scenarios and dependent upon relationship of different parameters such as water depth, wave period,

Therefore, the most critical limitation of current designs

studies on floating breakwater, the lower the resulting attenuate waves. Armono, H.D., (2004) concludes that increased. When wave height increases (given a water

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It will not be effective in water depths where the wave structure does not interact with the reef units. Scaling the units up to reach effective height will be costly and use more material for manufacturing. Potential to address this issue is by aggregation of units. But due to the variability of wave properties (height, length, period) and water depth (tide changes), the system design must be able to adapt to these variables.


Incident Waves

Wr

Lr

Flow Patterns

Fig.3.1.1.2 -14

Y

Four Types of Submerged Breakwater Arrangment and Resulting Current Patterns Adapted and Redrawn from Armono (2004)

Shoreline

Plan View

Submerged Breakwater

Submerged Breakwater

Incident Wave

Incident Wave

Fig.3.1.1.2 -15 Transmitted Wave

Transmitted Wave Non-conventional arrangement of submerged breakwaters. By aligning the reefs longitudinally

Conventional Arrangement

Non-Conventional Arrangement

energy than the conventional lateral Adapted and Redrawn from Armono (2004)

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3.1.1.3

PRINCIPLES AND PARAMETERS CONCLUSIONS

T

wo existing wave attenuation systems are investigated to gain understanding on what characteristics, principles and parameters govern the wave reduction capability of these systems, and what can be abstracted for setting of design strategies and design application. Precedents from coastal biological systems, and man-made structures such as the morphology as the key factor for effective wave reduction performance. However, there are variation in strategies observed from different scales. At a local scale, unit morphology becomes the focus. Density, porosity properties contribute to generating friction to create turbulence and micro-currents similar to the tangled roots of mangrove trees, â&#x20AC;&#x2DC;branchesâ&#x20AC;&#x2122; and shapes of corals, and shoots of sea grass. Material properties are focused more on reducing the stress on its own structure, as parts are allowed to flex or even break when reaching certain thresholds. In a larger scale, these smaller units cluster together, to form a larger overall morphology. Only at this point the Wave attenuation is influenced by the dimensions of the formed structure and its overall roughness in relation to the given wavelength and wave period. Area coverage,

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variation in patterns and aggregation, and positioning are important parameters. This is evident in design of floating breakwaters, and reef, mangrove forest and salt marsh systems. Another important principle in wave reduction systems is submergence, which considers the depth of water or depth of placement of the system. This affects how much it obstructs the wave column. Most coastal biological systems are rendered ineffective once water levels rise beyond its effectiveness to affect the structure of founded breakwaters. Floating breakwater is seen as the adaptable solution to changing water levels. Therefore, these systems provide good insight and background knowledge when considering wave reduction system design that adapts to different context conditions. Wave attenuation is always dependent on the morphology and environmental scenario which are very non-linear. For this dissertation however, the goal is to simplify into having a basic understanding of the principles and relationships between parameters. These will be further investigated in the next section 3.2.1 Experiments and applied further in design strategies in Chapter 4.


Corals & Coral Reefs

Mangroves and Mangrove Forests

Coastal Biological System

Saltmarsh & Seagrass

Floating Breakwater

Wave Attenuation Systems

Man-Made Coastal Structures

Scales of Application

Unit Morphology

Local

S

D

L

W

Growth and Aggregation

Porosity

Ht

Unit Density

W

+W

System Pattern and Aggregation

GLOBAL

Hi +d

Width of Structure

Depth and Rigidity

Structure Critical Condition

Distance (d)

Differentiation

Aggregation Density

Wave Direction

Width (w)

Position

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3.1.2

TEST SITE INFORMATION AND ANALYSIS

Sha’ao Bay Sha’ao Bay is one of the important bay that provides cucumber, kelp, etc. Being located on the edge of the coast of Ningde City, it is influenced by the wave and wind from the East China Sea directly. In this sea area, and engage in raising marine livestock. On the land, there are three villages evenly distribute nearby coastal line with almost 10,000 people live there. People has been sharing the phenomenon resource from this semiclosed bay since hundred years ago.

Fig.3.1.2 -1 Site Dimensions (Opposite) A 2.1km by 0.9km area will be used for the texting area, which within a 3.5km by 1.7km semi-closed bay.

94

For the purposes of this project, a holistic design strategy was developed based on environmental data, hydrological analysis that include wave and tidal study, and demographic information that shows the

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

aquaculture industry network. According to historical data, the Sha’ao Bay has been involving in aqua farming since 10th century around Tang dynasty. The surrounding villages were also taking place in aquatic related business, such as raft repair factory, fodder supply chain, etc. Nowadays it has been transformed from random culture activity to a commercial aquatic production district, and it is still expanding into an unimaginable settlement. However, the mass expansion frequent outbreaks of many problems. Therefore, the design team choose this bay as the test site to attempt the proposed strategies.


area

location

dimension

Shaâ&#x20AC;&#x2122;ao bay Test Site

3.5 X 1.7 (km) 2.1 X 0.9 (km)

0m

0 35

0 10

2

m

0m

90

00

17 m

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3.1.2.1

SITE CONTEXT & HYRDODYNAMIC CONDITIONS village radius:1km

1

port site

2

3

Fig.3.1.2.1 -2 Network Analysis & Transport The diagram shows the location of the site and surrounding villages and ports. Approximately within 1 kilometer people can access to the is the most crucial part in terms of connection at the sea. There are three types of transport that commonly be used at the site.

speed ship

30(knot)/55.6km/hr

cargo ship

15(knot)/27.8km/hr 10(knot)/18.5km/hr

Existing Network and Context In terms of network nodes in the sea area, the port has

maximum 10 minutes in a normal wave situation by a

raft settlement. Presently, there are three villages with four ports distributed around the bay, which transfer

the transportation time will double in the condition of shipping.

harvest that trade to markets. Almost 10,000 people live around Shaâ&#x20AC;&#x2122;ao Bay and mainly work on the aquatic related business.

The type of transportation way can catalog in a list of ship function. Speed ship is the most common Cargo ship mainly transports aquatic equipment and

The approach concerning the network across the site raft settlement. Being located the transport node will take into account the close distance from the edge of the site to those ports and wave impact level. The distance between site and ports is within 1 kilometer that take 96

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

live on the sea, which is not essential in a case of rooted


contour

0

-10

-30

(m)

0

-10

-30

(m)

intertidal zone contour site intertidal zone current site current

zone

Fig.3.1.2.1 -3

3.8 %

intertidal zone zone 0 - 10m intertidal zone 10 - 60m 0 - 10m

8.9% 3.8 % 87.3% 8.9%

This diagram shows the bathymetry of the bay and the percentage area of each depth of the sea. It not only helps to locate the site position but also understand the exact

10 - 60m

87.3%

management.

Low Tide

Tidal Range : 4.8 m

Low 0m Tide

Tidal Range : 4.8 m

-10m 0m -30m -10m High Tide -30m

High 0m Tide -10m 0m -30m -10m -30m

Normal wave situation current velocity 0.8m/s wave high 2m wind velocity around 5m/s.

Storm wave situation

current velocity 2m/s wave high 6m wind velocity around 35m/s

Fig.3.1.2.1 -4 Tidal Range Data: Tidal change has become an issue that affect aquaculture process. In this bay, the range can exceed 5 meters difference.

Hydrology Conditions Waves and Tides are condition that the design team considers. It includes complex issues that integrate water circulation, wind direction, and water density. As far as the site analysis goes, the following three factors will be consider in setting strategies and designing: Wave height, tidal change data, and bathymetry data. The prevalent wind and wave are coming from the northeast direction, where is the mouth of this semi-closed a parallel position in order to minimize external force. It has been predicted the wave velocity reach 2m/s and 6m high with 35m/s wind speed in a storm situation (Chu, P. C., & Cheng, K. F. 2008)

Second, based on the tide data, the tidal change will have created many unique culture strategies by this substantial tidal change. And, it helps to exchange the sea water twice a day. It not only maintains the quality of sea water but also generates water movement that is essential for marine culture. Moreover, the bathymetry also influence the flow on the water surface and the wave characteristics, especially when the tidal range is greater than one tenth of the bayâ&#x20AC;&#x2122;s depth then tidal flow scenario needs to be taken into account more carefully. 3.0

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3.1.2.2

PRECEDENTS FROM SITE

Fig.3.1.2.2 -4 Fish Raft Settlements settlement that be consisted of a square unit and aggregated into a huge culturing settlement.

Existing Programs Raft cage culture is the traditional way in aquaculture in China. There are very few large-scale aquaculture corporations domestically; most of the production comes from millions of small-scale farms owned by individual

disease and parasitic infections. Although tidal change could bring clean sea water, the speed of clearance by nature is always slower than the pollution that people emit into the sea.

to adapt most sea conditions and provide stable harvest. quality and repair. The material used for construction are collected from the local market, which include bamboo, wooden boards, steel pipes and polyvinyl chloride or nylon nets. However, the disadvantage of it is most of them easily be destroyed during storm situations. These cage types has three problems: First, there is limited space for future expansion while more and more cannot withstand typhoon in some circumstances. is threatened by annual disasters. Third, inshore cage farming causes severe environmental pollution through 98

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settlement. Fish raft morphology has been popular located in any environmental scenario at the same time the consideration also take into account the dimension of the width of the path for different types of boats. The spatial consideration at the sea has its guideline although it still base on human activities. Depending on the investigation that inform the design team more possibilities to establish this future settlement.


program residential area

no. 1 (3*3m) 50 fodder mixing area 1 2 3 (winter) 5

Fig.3.1.2.2 -5

that has been using for many number of cages and labors by season.

program

Ht. 3 1

sea level

0

5

Fig.3.1.2.2 -6 Fish raft section dimension The section diagram shows the

sea water

5 min.depth

boat path

6m

transport

path(m)

cargo ship

40

speed boat

6 5

10

raft. That has informed design team to consider the depth of the sea and tidal issue.

Fig.3.1.2.2 -7 The width of path for transports Network system has been existing inside the settlement. People leave space automatically when

6m

boat path

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3.1.2.2

PRECEDENTS FROM SITE

position A Year

1

position B 2

3

4

5

6

7

8

9

10

Position

Fig.3.1.2.2 -8 Timetable for ranching migration schedule in every three years. The new place where with more suitable sea condition and fresh sea quality.

Sea ranch strategy characteristics that happen in every three years. Due to the culture location runs out of nutrients that supply for marine livestock and the area contains too many pollutants by the waste of culture herd. Fishermen need to look for a new location when they are still managing According to the empirical studies, the average migration period happens once in a three years. The consideration is not only the nutrients are exhausted in that area but also correlated the period of culture schedule. Throughout the aquaculture data, each species has a certain growth schedule, for example, abalone harvest

have to confront a new issue that appear which is lacking culturing space. In the purpose of getting better area with strong wind and high wave in terms of the shortage of culture area. Otherwise, continuing stay in the same place will lead to the decrease of aquatic production. Material duration is another issue that have to address before it cannot sustain the environmental impact. essential work with the period movement. Although

years at least. Therefore, the ranch behavior can be

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2008

2011

2013 Fig.3.1.2.2 -9 The migration movement in years This three images has shown a sigmove in and people migranted from other sea area.

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3.1.2.3

CONCLUSION

Fig.3.1.2.2 -10 settlement pattern Fish rafts are following the hydrological conditions to arrange the orientation, which based on the ancestor knowledge and itself experience.

Conclusion Through research and resource analysis, this site has informed the design team varied possibilities that can use in the design strategy. This project will develop under the integration of these four investigations that ranching while also take into account the methods limitation that can apply the design strategy. As the study the commercial purpose. Fishermen are looking for the impact plot that is related to the distance between the coastal line and offshore danger line. Moreover, the is varied that according to the features of the locationâ&#x20AC;&#x2122;s circumstances.

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dynamic system that floats with the wave, the limitation of movement still is a restriction that conduct the overall settlement. However, the capability of movement is easier than the common situation in term of a rooted construction. As the concern that sea area is not a normal human place to live, the opportunity has been found people have the chance to accommodate those conditions and complement the sea urban settlement system perfectly.


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3.2 EXPERIMENTS This section presents simple experiments done to test the different principles and parameters abstracted from the precedents of wave attenuation systems. The aim is to identify important parameters, characteristics or effects that contribute to wave reduction. Also, through these experiments, methods are tested if they are effective or not to develop the strategies for the project. All experiments are done on digital and computational platforms. Two main principles are investigated - Porosity (3.2.1) and Density (3.2.2). These are based on the biomimetic abstraction from coastal biological systems and In testing for wave reduction (3.2.4), it is important to simplify and contextualize the experiment because of its non-linearity and complexity. Principles learned from floating breakwaters and published results from other experiments, help inform the algorithm set-up and limitations for design evaluation.

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3.2.1

POROSITY EXPERIMENT

Surface / Volume

Surface/Volume relationships to velocity Surface / Volume

Surface/Volume relationships to velocity

Parameters Parameters r 1m

1m

0.2 m3 1m

1m

1m

0.2 m3

X

X

1m

X

X

r

R1

R1

R1 X S R2 r

Radius(m) R1 Radius(m) Grid size (m) Grid size (m) X area Surface (m2) S Pore size Surface radious(m)area (m2) PoreR2 throat radious(m) Pore size radious(m)

r

Pore throat radious(m)

Constant value

Fig. 3.2.1 - 1

Volume (m3) : 0.2 m3 Constant value Initial velocity : 10 m/s Cube Dimension : 1 m Volume (m3) : 0.2

Initial Experiment design parameters and constant values.

m3 Initial velocity : 10 m/s Cube Dimension : 1 m

Hydraulic conductivity and Drag force In nature, coral colony intervenes the water flow by its morphologies, which reduce water velocity by generating turbulence for nutrition exchange. The principle of this complex structure responsible for such action are the water permeability property and the drag effect. The experiments aim to explore the relationship between and the amount of velocity reduction after liquid passing through the system. The constant factors are the total material volume, cube boundary dimension and Initial velocity. The material volume remains constant to test how different parameters could affect the velocity reduction without adding more material. The other environmental factors; boundary conditions and water viscosity remain constant throughout all experiments. The permeability property and skin drag effect are tested in Experiment 1 while the form drag effect principle will be tested in Experiment 2 and Experiment 3.

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The permeability properties are tested in Experiment 1 by changing the parameters of grid size reducing the pore radius in three steps. The hypothesis is that the velocity reduction rate increase when the grid size decrease. The property of skin drag effect is also considered in the same set experiment as the surface area increases throughout the process. The water velocity differences hypothetically increases when surface contact with water increase. Experiment 2 aims to test roles to change velocity reduction without adding more material. The principal of exposed surface is also tested in Experiment-3 on differentiated geometry.


Individual 1 Surface area(m2):4.9633 Surface/volume:24.816595 Pore R1/r : 1.800 Surface exposed:0.82722

4.963 24.816 1.800

Individual 2 Surface area(m2):8.272198 Surface/volume:41.360992 Pore R1/r : 1.986 Surface exposed:0.82722

8.272 41.360 1.986

Individual 3 Surface area(m2):11.581078 Surface/volume:57.9053 Pore R1/r : 2.097 Surface exposed:0.82722

11.581 57.905

Fig. 3.2.1 - 2

2.097

Experiments 1 variable values, arrangement and patterns, Velocity reduction results.

Experiement1 Skin drag and Permeability

14

12

10

Velocity (m/2)

Skin drag The experiment aims to explore the velocity different in relation to the ratio of surface area (m2) per volume (m3). Surface area constantly increase; 1.9,3.5,3.8 but velocity differences from initial velocity and the minimum velocity after passing through the system is not linear; 4.96 ,8.27,11.58. The minimum velocity also occurs at the same distances for all three sets. This conclusion is supported by the Skin drag force mathematic equation that Skin drag force has direct relationship to v2 and surface area contact with water.

8

6

4

2

Permeability The changing parameter of grid size relates to the ratio of pore size radius and pore throat radius, which The conclusion is that the ratio of pore radius and pore throat radius (1.8 , 6.5 , 6.2) and the velocity differences(1.9,3.5,3.18) share the similar trend.

0

1

2

3

4

5

6

7

8

9

10

Distance (m) Distance (m)

Legend

1 2 3

Within the boundary Behind the boundary Distance of minimum velocity Individual 1 Individual 2 Individual 3

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3.2.1

POROSITY EXPERIMENT Individual 1 Surface exposed:1.654 Surface area(m2):4.9633 Exposed area/ area: 0.33 Pore R/r : 2.921

4.963 24.816 1.800

Individual 2 Surface exposed:1.654 Surface area(m2):8.272 Exposed area/ area: 0.199 Pore R/r : 3.105

8.272 41.360 1.986

Individual 3 Surface exposed:1.654 Surface area(m2):11.581 Exposed area/ area: 0.142 Pore R/r : 3.213

Experiments 2 variable values, arrangement and patterns, Velocity reduction results.

57.905 2.097

Experiement 2 Form drag The purpose of the experiment is to test the impact of exposed surface area on the velocity differences by changing the arrangement. According to the staggered position of the spheres, the exposed area is 2 times higher than that of the experiment 1(0.8277 in Experiment1 and 1.654 in experiment 2). The velocity reduced dramatically compare to experiment 1, accounting for 8.5,6.5, 6.5, while the values are 9.7,6.5,1 in experiement2. The conclusion is that with the same volume, the more exposed area facing water vectors, the more velocity reduced. This result is supported by the equation of form drag force.

14

12

10

Velocity (m/2)

Fig. 3.2.1 - 3

11.581

8

6

4

2

A

The new arrangement not only changes the constant value of surface exposed area, it determined the value increases the ratio between both values from 1.802.09 in experiment 1 to 2.921- 3.213 in experiment 2. Therefore, the dramatically reduce of water velocity after passing through the arrangement is the result of the increase exposed surface area and the ratio between Pore size radius and Pore throat radius.

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0

1

2

3

4

5

6

7

8

9

Legend

1 2 3

Within the boundary Behind the boundary Distance of minimum velocity Individual 1 Individual 2 Individual 3

10

Distance Distance(m) (m)


Individual 1 Surface exposed(m2): 2.30 Surface area(m2) : 5.10 Exposed area/ area : 0.45

2.30 5.10

0.45 v

Individual 2 Surface exposed(m2): 2.34 Surface area(m2) : 5.00 Exposed area/ area : 0.47

2.34 5.00

0.47 v

Individual 3 Surface exposed(m2): 2.41 Surface area(m2) : 4.92 Exposed area/ area : 0.49

2.41 4.92

0.49 v

Individual 4 Surface exposed(m2): 2.42 Surface area(m2) : 4.82 Exposed area/ area : 0.50

2.42

Fig. 3.2.1 -4

4.82

Experiments 3 variable values, arrangement and patterns, Velocity reduction results.

0.50 v

Experiement 3 Form drag and geometry 25

20

Velocity (m/2)

The principle concluded from Experiment 2 is then brought to Experiment 3 on single geometry and what is the potential to apply as a system integrating all experiment together. The result shows the same trend with the aggregated pattern in Experiment 2 that the higher exposed area or more surface area reduces more velocity after water passes through. Sphere has the

15

10

5

For the application of three experiments, the staggered pattern with smallest grid size with sphere geometrical units should be the most effective velocity reduction grid sizes and the pattern of aggregation. The next experiment then could focus on different pattern and volume of material for the application in different behavioral needs.

0

1

2

3

4

5

6

7

8

9

10

Distance (m)

Legend

1 2 3 4

Within the boundary Behind the boundary Distance of minimum velocity Individual 1 Individual 2 Individual 3 Individual 4

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3.2.2

DENSITY EXPERIMENT

Experiment Boundary Conditions 50m

50m

1 Unit

2500 m2

Spacing

No. of Units/ Area Covered (m2)

Width/ No.of Rows

Fluid Type : Sea Water

Depth

Length

1 Modular/ Aggregated Unit

Velocity: 10m/s - Storm Surge Equivalent Bounding Box: 100m x 200m

Variables No. of Units: Test 1 = 100 Test 2 & 3 = 64 Diameter of Units: Test 1 & 2 = 2m Test 3 = 4m 1m x 3m Maintain equal spacing between unitsas much as possible

Fig. 3.2.2 -1 Boundary conditions and variable inputs and set-up of experiment

Parameter Testing and Criteria The previous experiment on the principles of Porosity concerns more on the amount of surface area in contact with the body of the material. For Density, the scale moves a level higher, pattern and arrangement of units becomes a consideration. This set of experiments uses three parameters as variables to test its relationships. It considers: 1. The number of units per area covered 2. The pattern arrangement - where the experiment sets up a linear, staggered or random arrangement of units. rectilinear was tested. By using computational fluid dynamics (CFD) simulation software, the objective is to identify how much velocity is reduced after passing the fluid through a given area

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of units. To analyze and compare results, graphs and CFD output are observed with the following criteria: 1. If there is an increase or decrease in velocity of flow upon impact of the fluids to the units. 2. If from the initial velocity, how much was increased and/or reduced after passing through the area of units; 3. And what is the effective value and distance of velocity reduction given a pattern type or area covered.


200m TEST 1

Size: 50mx50m

TEST 2

No. of Poles: 64

Spacing On-Center: 6.25m

Diameter: 1.00m

3

TEST 3

TEST50mx50m 1 Size:

Size: No. of 50mx50m Poles: 64

No. of Poles: 100 Random Arrangement

Spacing On-Center: 5.55m

Diameter of Pole: 1.00m

TEST 3

Size: 50mx50m

4

100m

1

No. of Poles: 100

2

TEST 2 - B

TEST 3 - B TEST 3

Size: 50mx50m

No. of Poles: 64

Spacing On-Center: 6.25m

Diameter of Pole: 2.00m

Surface Exposure to Flow Vectors

Porosity & Density

Surface Area vs. Volume Arrangement / Location

Geometry Roughness

Friction

reduction, and shows very minimal impact increase be perpendicular to the velocity direction, and a linear pattern already makes it effective. A random pattern, scatters the flow, or redirects the direction, resulting in very small boundary layer. But most effective is the staggered pattern in reducing the flow within the system. It is similar to performing as a whole 50x50m unit.

A knowledge of how these parameters affect velocity reduction is important especially when designing a system. Initially, hypothesis is that the larger number of units, and the larger the size of each unit will be the most effective in velocity reduction. (Continued p.94) Arrangement /

Effective Depth (Site B

Geometry Roughness

Having fewer units, but in staggered or random pattern achieves almost similar effects with more units in a linear pattern. It shows minimal increase in velocity. This may be due to the spacing or openings,

Surface Exposure to Flow Vectors

Friction

The varying the number and pattern of units has more influence in velocity reduction compared to increasing the size or dimensions of the unit as evident in all Test 3 of Experiments A, B and C.

Fig. 3.2.2 -2 Criteria For Analysis and Comparison 1. Impact Velocity Increase/ Decrease 2. Effective Value & Distance of Velocity Reduction 3. Boundary Layer / Area Covered by Reduction 4. Graph Plot points Location for all experiments

allowing the fluid to flow easily but then restricted by the staggered pattern. Porosity & Density

TEST 3

Size: 50mx50m

No. of Poles: 64 Porosity & Density

Spacing On-Center: 6.25m Effective Depth (Site Bathyme

Diameter of Pole: 2.00m

Effective Depth (Site Bathymetry)

leaving the system. Also it shows a wider and longer boundary area of reduced velocity.

TEST 3

Size: 50mx50m

No. of Poles: 64

Spacing On-Center: 6.25m

Diameter of Pole: 2.00m

TEST 3

Size: 50mx50m

No. of Poles: 64

Diameter: 2.0m

Random Arrangement

In considering the pattern arrangement of units, staggered and random patterns show an increase in velocity upon impact of fluid to the system, but

TEST 3 TEST 2

Size: 50mx50m Size: 50mx50m

No. of Poles: 64 No. of Poles: 64

Diameter: 2.0m Spacing On-Center: 6.25m

Random Arrangement Diameter: 1.00m

TEST 2

Size: 50mx50m

No. of Poles: 64

TEST 3

Size: 50mx50m

Spacing On-Center: 6.25m

No. of Poles: 64 Diameter: 1.00m

Random Arrangement

By analyzing the experiment results (shown in next page), the following can be deduced: •

Spacing On-Center: 5.55m

TEST 1

Size: 50mx50m

No. of Poles: 100

Spacing On-Center: Size: 5.55m 50mx50m

Random Arrangement

No. of Poles: 64 Diameter of Pole: 1.00m

Diameter of Pole: 1.00m

TEST 3

Size: 50mx50m

No. of Poles: 64

Random Arrangement

TEST 1 - A

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3.2.2

DENSITY EXPERIMENT Linear & Staggered Pattern (A) TEST 1 Basic Pattern

TEST 2 Reduced Units

TEST 3 Double Unit Size

Random Pattern (B) TEST 1

TEST 2

TEST 3

TEST 2

TEST 3

Rectilinear Section (C) TEST 1

Velocity Magnitude (m/s)

<100

50 30 10 0 Fig. 3.2.2 -3 Three Experiments Testing Density

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Velocity reduction beyond system

Velocity reduction through system

Velocity Magnitude (m/s)

40

30

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3.2.3

CONCLUSIONS

20m

10m

15m 50m 25m 50m

200m Fig. 3.2.3-1 200m

Other small experiments testing clustering and larger scale application of density principles

(Continued from p.91) However, based on the results deduced, velocity reduction is dependent more on the pattern, and followed by the number of units in a given area. And least influence is the size of the units. Having a staggered or random pattern and keeping sizes of units at an appropriate scale helps reduce velocity as it impacts the system and creates a wider boundary layer of low velocity. The other experiments that followed test multiple 50mx50m areas side by side, and long concave or convex areas either spaced 10-25 meters apart. It was realized that scale is indeed an important consideration. When considering a larger boundary condition, the effects of the individual units

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become negligible, and instead the 50x50m area becomes a â&#x20AC;&#x2DC;unitâ&#x20AC;&#x2122; itself to reduce velocity. Therefore, the larger the area of application or boundary condition, components. But instead, the whole becomes more


Local

Regional

?

Identify what is/are the: 1. Effective distance from shore 2. Distance to next â&#x20AC;&#x2DC;layerâ&#x20AC;&#x2122; of units 3. Velocity range per zone to accommodate functions & programs 4. Effective depth to from sea bed 5. System dimensions and arrangement 6. 7. Context / Site Area

Global

?

Floating / Submerged System

Zone 4

7

Zone 3 Zone 2

3 Zone 1

1

5 5

2

Fig. 3.2.3 -2

6

Schematic Diagram of parameters to consider in applying the density principle in a cluster (regional) or global scale. Drawing Not to scale

4

Porosity and Density Experiment Conclusions Initially, the dissertation team, thought of developing a component based material system. Porosity and considering the friction and turbulence it can generate to aid reduction of fluid flows. But through testing, and analyzing the site conditions, the team begins to question the initial strategy, of developing a component based wave reduction system as the main focus of the dissertation. A decision was made to shift priority to a larger scale where the pattern and arrangement of the larger unit is believed to be more appropriate and strategies further. Although, the strategies for the wave reduction units are still an important consideration, the study scope will look more into principles and

morphology design, instead of in-depth material and fabrication development. Another aspect to be reconsidered is the horizontal flow of water may only be applicable when dealing with currents or storm surge, but frequent occurrence of waves are oscillating vertical movements. And this cannot be tested with the CFD software used. Due to the limitations of simulation softwares, the next experiments in Section 3.2.4 attempts to develop a parameter relationships studied from published results and wave equations. And it starts of from the larger scale considering pattern and arrangement of wave reduction units. 3.0 RESEARCH DEVELOPMENT

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3.2.4

WAVE REDUCTION SIMULATION EXPERIMENTS 0

-10

-30

(m)

contour intertidal zone

0

-10

-30

(m)

site intertidal zone

current

village

1

radius:1km port site sea floor contour current

TEST SITE

zone

zone intertidal zone 0 - 10m 10 - 60m

2

intertidal zone

3.8 %

0 - 10m

8.9%

10 - 60m

87.3%

Low 3.8 %Tide

3

Tidal Range : 4.8 m

N

Site

8.9%

0m 87.3% -10m -30m

High Tide 0m -10m -30m Area Suitable for Aquaculture Development

Context Abstraction for Experiments To contextualize the experiment, a test site was selected as presented in Section 3.1.2. By analyzing site data, such as the tide data and bathymetry, the dissertation team selects a portion of the area where it is appropriate to test and develop their strategies. The site was then abstracted into a 2100m x 900m rectangular area with a grid of 30mx 30m cells. The sizing of the cells and an appropriate minimum size for breakwater at this scale of testing. The highest recorded wave height

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and prevailing wave direction are used as experiment conditions. This will be the resolution and the basis where tests and algorithms are run in this chapter, and in testing of design inputs for floating settlement organization in Chapter 4 - Design Development.


Land-Based` Village

2 900m Near-Shore

Cell Size 30m x 30m

Land-Based` Village

2100m

â&#x153;&#x201D;

Resolution 2100 cells

In-Shore Area

Land-Based` Village

Off-shore Area

1

3

N

Off-Shore

Wave situation Normal:

Wave Direction

current: 0.8m/s wave height: 2m Storm: current: 2.0m/s wave height: 6m Tide Range: 5m

Fig. 3.2.2 -3 Abstracted Site for Digital experimentation and as interface for simulation

-10m

-15m

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3.2.4.1

TESTING LATTICE - BOLTZMAN METHOD

Collision Step: Streaming Step: Fig. 3.2.4.1 - 1 Collision and Streaming Equation

Lattice - Boltzman Method Lattice Boltzmann methods (LBM) or Thermal Lattice Boltzmann methods (TLBM) is a class of computational fluid dynamics (CFD) methods for fluid simulation. Instead of solving the Navierâ&#x20AC;&#x201C;Stokes equations, the discrete Boltzmann equation is solved to simulate the flow of a Newtonian fluid with collision models such as Bhatnagar-Gross-Krook (BGK). By simulating streaming and collision processes across a limited number of particles, the intrinsic particle interactions evince a microcosm of viscous flow behavior applicable across the greater mass.(Hamrang, 2014) To the advantage of setting up the algorithm, many softwares use it to deal with flow dynamics and hydraulic scripting language. However, there are some software and libraries written in other language, for example Java and Python. 118

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Python is one of the most advanced programming language that allows user to spend least time to achieve the complex target. The professional CFD software Document) In this initial experiment, LBM method will be implemented into Rhiceroces, one of the most widely used architecture modelling software. The Algorithm will be written in IronPython with the help of NumPy and SciPy library.


Iteration = 0

Iteration = 120

Iteration = 240

Iteration = 360

Iteration = 480

Iteration = 600 Fig. 3.2.4.1 - 2 LBM D2Q9 model Curl experiment using Python for Rhinoceros

Conclusions A simple simulation was run using the algorithm written in Rhino Python environment. Without the OpenGL optimization, GPU cannot be used to speed up the simulation and the Python environment in Rhino is IronPython which is much slower than the pure Python environment. However, acceptable results are still achieved as shown the Figure 3.1.C. Based on the precedents from the CFD research, the lower viscosity, the lower precision. Therefore, once water properties are applied to the algorithm, the resolution of the result will be reduced. And the simulation size was scaled up, leading to an even lower resolution. In order to achieve a proper result, an alternative method is needed to be explored.

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3.2.4.2 EXPERIMENT 1- WAVE IMPACT AND PLATFORM PATTERN ARRANGEMENT

Wave Impact Evaluation and Platform Arrangement Limitation of LBM simulation was found during the initial experiment. And the principle of sea wave movement (vertical and oscillating) is different from the water particle movement in river (horizontal current flows). It is mainly the periodical up and down movement with wave energy transfer. The target is try simulate how different arrangement of floating platforms can provide the corresponding wave energy reduction. The simulation is an abstraction once using the water particle as the basic unit and apply it to the 2100 meter by 900 meter site. Physical simulation and result is necessary to simulation. In order to achieve acceptable simulation resolution. A group of published physical wave reduction experiments papers are referenced and its result has been implemented into our simulation. Similar scale of wave height, wave length, floating platform size are implied. Different combination of platform produces different wave risk pattern, at the same time, the location 120

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Once the proper evaluation strategy has been set up, the the help of computation algorithm. was developed to calculate the wave reduction and generate the wave impact pattern. The simulation iteration can be described as two main steps: Collision: Once wave collide with floating platform, reduction reduction of wave height. Streaming: after collision, sea wave move to the next place and then start the next iteration.


Variation of position or orientation of wave reduction units

D i re c t i o n of Wave

Wave at 6m Height

Platform/s

Wave Interaction with platform

D i re c t i o n of Wave

Reduced Wave Height Values

Fig. 3.2.4.2-1 Platform Placement and Orientation and simulation diagram

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3.2.4.2 EXPERIMENT 1 - WAVE IMPACT AND PLATFORM PATTERN ARRANGEMENT Experiment 1 - Cases

2100m

900m

Wave Height High 6.0m

Low 0.0m

Wave Direction Case 1: Wave Height Range: 0.006839m to 6m Area Coverage: 13.76%

Case 2: Wave Height Range: 0.13958m to 6m Area Coverage: 14.76%

Case 3: Wave Height Range: 0.00977 t0 6m Area Coverage: 14%

Objectives Different arrangement of platform has been evaluated. Wave impact pattern has been generated and examined.

Inputs and Variables

True

Coefficient Calcuation

Apply

Wave Collision Check

Incident Wave Height - 6m 30 points - Location of Cluster Points Clustering of platforms

Wave Streaming

False

iteration i(i< site depth)

Outcomes Arrangements of the Platform and wave impact map of the site

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Case 4: Wave Height Range: 0.004788 to 6.0 Area Coverage: 14.57%

Case 5: Wave Height Range: 0.006839m to 6m Area Coverage: 14.76%

Case 6: Wave Height Range: 0.000394 to 6.0 Area Coverage: 13.85%

Experiment 1 - Conclusions algorithm, the real-time value and graphic feedback is achieved, which later on will contribute to the evaluation loop and integrate with other methods for design. The wave reduction algorithm was written in Python. However, the calculation speed start to slow down while we keep on introduce new variable to improve the algorithm. In order to reduce the calculation time, the whole algorithm has been rewrite in C#. The speed turn our to be ten times faster than the original one. (See Appendix for Scripts) Different arrangement of platforms has been tested to generate the corresponding wave impact pattern

Six different cases with corresponding platform arrangement have been assessed. The average wave risk is highly affected by the arrangement of the zone(close to coastal) contributes very little compared with rest of the zone. Based on the physical experiment ran by G.H.Dong and his colleagues in Dalian University of Technology, breakwater compare with the length of the wave. Second, the height of the wave. Third, the rigidity of the platform. discussed how to select the higher rigidity individual in morphology research (Chapter 4.1). We only discuss the rest two factors in this and flowing experiments.

The results help the team to understand the logic of wave impact transfer. 3.0 RESEARCH DEVELOPMENT

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Trans

0.4 0.2

3.2.4.3 EXPERIMENT 2 - CONSIDERING WAVE EQUATIONS & RELATIONSHIPS 0 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 H/L

0.1

0.11

WAVE HEIGHT, BOARD WIDTH H=2.5m B=32m H=4.5m B=32m H=2.5m B=100 H=4.5m B=100 H=6.0m B=32m H=6.0m B=100

32m-100m (150m)

board

10m

net

Section

Transmission coefficient

1 0.8 0.6 0.4 0.2 0 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 H/L

0.11

WAVE HEIGHT, BOARD WIDTH H=2.5m B=32m H=4.5m B=32m H=2.5m B=100 H=4.5m B=100 H=6.0m B=32m H=6.0m B=100

Fig. 3.2.4.3 -1

32m-100m (150m)

Experimental Breakwater and Parameter relationships from Dong. et.al (2008)

board

10m

Wave Equations As learned from the study of waves in Chapter 1, wave parameters and characteristics change and are dependent largely on the depth of the sea. Many research has been done to explore the relation between the wave period changes corresponding to the sea depth. Neumann and Gerhard list a group of equations that illustrate these relations in the book, Principles of Physical Oceanography, published in 1966.(Chapter 1, Fig. 1.3.1 -5 Wave Equations). While in deep water, the sea depth is more than four times of the wave length. The value of wave height and wave length is not affected by its depth. It just simply relates to the wave period and gravity. Once the wave reaches the shallower water, the seabed starts to affect the wave height and wave length. exploring these equations together with the physical wave reduction result. 124

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net

Figure 3.2.4.3-2 shows the gradually reduced wave length. In this experiment, the minimum wave depth is around 15m during the high tide condition. The wave breaking condition is not considered as the simulation waveSection reaches shallower water . As the experiment results show (p.126), within certain range, floating platforms perform better while deal with shorter wave periods than with longer period. It also performs better when in the shallower water. attempts to utilize the algorithms to apply the wave parameters, and equations. The next experiment, introduces objectives for evaluation the appropriate pattern for different wave cases


Wave height at 6m, Water depth at 20m

Wave height at 6m, Wave period at 10s

breakwater decreases.

breakwater also decreases due to longer wavelengths and wave periods at deeper waters.

Wave Direction

Wave depth at 20m, Wave period at 10s

When wave height is lower, it can still be reduced, however, the the percentage of reduction is less.

2100m

Wavelength Fig. 3.2.4.3 -2

>129m

900m

<35m

Off-shore

Near-Shore

From simulations and experiment number 2 and onwards, the wave equations are considered and applied to the algorithm. Based on the equations, the wave length is a very critical parameter that is affected by depth of water, the wave itself, and as input criteria of breakwater design.

-10m -20m

3.0 RESEARCH DEVELOPMENT

900m

125


3.2.4.3 EXPERIMENT 2 - CONSIDERING WAVE EQUATIONS & RELATIONSHIPS

2100m

900m

Wave Height High 6.0m

Low 0.0m

Wave Direction Case 1a: Wave period start from: 10s Wave length start from: 129.5m Wave height start from: 6.0 m

Case 1b: Wave period start from: 10s Wave length start from: 129.5m Wave height start from: 4.0 m

Case 1c: Wave period start from: 10s Wave length start from: 129.5m Wave height start from: 2.0 m

Wave length range(35.4m to 129.5m) Wave height range(0.28m to 6m)

Wave length range(35.50 m to 129.50m) Wave height range(0.24m to 4.0m)

Wave length range(35.48m to 129.5m) Wave height range(0.18m to 2.0m)

Objectives -Integrate wave equations -test relationshiop of parameters to system

Inputs and Variables One (1) Test Pattern Wave Period - 10s, 8s, 6s Wave Height - 6m, 4m, 2m

Deep True

Depth Check

Shallow

Coefficient Calcuation

Wave Collision Check

Outcomes Wave Length Range Wave Height Range

Wave Streaming

False

iteration i(i< site depth) New wave height and wave position

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Apply


Case 2a: Wave period start from: 10s Wave length start from: 129.5m Wave height start from: 6m

Case 2b: Wave period start from: 8s Wave length start from: 92.95m Wave height start from: 6m

Case 2c: Wave period start from: 6s Wave length start from: 56.2m Wave height start from: 6m

Wave length range(35.4m to 129.5m) Wave height range(0.28m to 6m)

Wave length range(28.37m to 92.95m) Wave height range(0.43m to 6.0m)

Wave length range(21.22m to 56.2m) Wave height range(0.12m to 6.0m)

Experiment 2 - Conclusions As discussed in Experiment 1, relation of wave length and platform width, together with the wave height are the two deeper study on the coastal hydraulic issues will provide a more practical result in Experiment-2 (Neumann and Pierson, 1966). Coastal sea wave length and period are dynamic parameters that change corresponding to the water depth. The implementation of this dynamic changing is necessary during the simulation procedure. Dynamic wave length has been implemented in the algorithm during the second experiment. Reduction water and shallow water. wave period with series of wave height has been test for comparison. 3.0 RESEARCH DEVELOPMENT

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False

3.2.4.4 EXPERIMENT 3 - IMPROVED CLUSTERING AND WAVE REDUCTION ALGORITHM iteration i(i< site depth) New wave height and wave position

Deep True

Depth Check

Shallow

Coefficient Calcuation

Apply

Second Axis Transfer

Wave Collision Check

Wave Streaming

False

iteration i(i< site depth) New wave height and wave position Wave Refraction with Platform

Direction Wave

of

Step 1

Step 4

Step 7

Step 10

Wave Reduction Algorithm Improvement In the actual conditions, wave transfer and movement is not just go in one direction. This is evident in the wave refraction phenomenon, once the wave encounters an obstacle, the wave will move past and around it. In this experiment, improvements have been made for the algorithm to aid the simulation in dealing with wave transfer along both X and Y directions. Both high-tide and low-tide conditions are also considered and evaluated. Based on the experiments, it is found that the proposed 30meter by 30meter floating the larger wave height and shorter wave length within the range of wave characteristics mentioned. A higher density of floating wave reduction units are also needed areas for settlement and aquaculture development.

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be carefully arranged after identifying the safety zones. However, it is not enough to just take the numerical results to determine which pattern is the most effective in wave reduction. The results return the lowest average height may not necessary mean the best option. What is more important is the extent or area which is within the safe threshold, such as 4 meters wave height or below. Also the clustering of the platforms can still be smarter and improved. Sizes may vary, and must respond to context wavelength, it can be larger towards the offshore areas where wavelength and wave height is


CASE 1 - CHANGE IN PATTERNS CASE 2 - CHANGE IN WAVE PERIODS

Wave Direction Case 1A Wave period start from: 10s Wave height start from: 6m

Case 1B Wave period start from: 10s Wave height start from: 6m

Case 1C Wave period start from: 10s Wave height start from: 6m

Wavelength range(37.02m to 141.55m) Wave Height range(0.93m to 6.0m)

Wavelength range(37.02m to 141.55m) Wave Height range(0.85m to 6.0m)

Wavelength range(37.02m to 141.55m) Wave Height range(0.96m to 6.0m)

Wave Height High 6.0m

Low 0.0m

Case 2A Wave period start from: 10s Wave height start from: 6m

Case 2B: Wave period start from: 8s Wave height start from: 6m

Case 2C: Wave period start from: 6s Wave height start from: 6m

Wavelength range(37.02m to 141.55m) Wave Height range(0.97m to 6.0m)

Wavelength range(29.59m to 99.82m) Wave Height range(0.82m to 6.0m)

Wavelength range(22.13m to 56.14m) Wave Height range(0.63m to 6.0m)

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3.2.4.5 WAVE REDUCTION EXPERIMENTS CONCLUSION Near Shore

0

900m

-10

-30

(m)

Village 1

SITE

Low Risk Areas

Zone 5

Potentially safe zones for aquaculture and settlement aggregation

Village 2

Village 3

Context Map

High Risk Areas

Zone 4

2100m

Areas not suitable for aquaculture and settlements, will serve as buffer zone for high waves

Zone 3

Wave Height High 6.0m

Low 0.0m

Zone 2

WAVE CASE:

Wave period start from: 6s Wave length start from: 56.2m Wave height start from: 6m Wave length range(21.22m to 56.2m) Wave height range(0.12m to 6.0m)

Zone 1

Wave Direction

Off-Shore

Variables • Wave Reduction System Pattern • System Unit Clustering Boundary Conditions /Inputs • •

Highest Wave Height (Max): 6m Starting Wavelength: 56m

Objectives • • •

130

Identify high-risk and low risk areas Indentify Level of safety Zones 1- 5 Pattern Arrangement of Wave Reduction Platforms

By testing different methods and applying wave reduction principles and equations to an algorithm, it is possible to conduct wave reduction simulations in the same interface where design strategies are to be developed. It is important to note that this wave reduction experiments testing of methods and patterns are done simultaneously with the development of the Wave Reduction Unit Morphology Design. Results of potential performance capabilities of the units and observed results form the site context experiments inform one another’s development. Although it is not yet fully integrated, and as of this point, only considers the aggregation of units in context application. More of the Wave reduction unit research on the next chapter.

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015


(

AMBITION

Infrastructure

)

(

DESIGN STRATEGIES AND DEVELOPMENT

Chapter 4.1 Wave Reduction System

Principles and Parameters

)

Chapter 3.2.4 & Chapter 4.1 & 4.2

Wave Reduction Unit Morphology Design

Wave Reduction Unit Pattern Arrangement

+W

+d

+

Chapter 4.2 Floating Settlement Organization Fishing boat

Life Aquaculture

Raft Aquaculture

Habitat

Floating Settlement Organization Logic

Multiple Design Levels for Organization Network Zoning Program

ADAPTIVE FLOATING SETTLEMENT Developed floating settlements organization logic based on wave reduction and aquaculture activity

Density

This diagram provides a design process overview for the next chapter - Design Development. After conducting analysis and experiments of principles and methods, the study for wave reduction and information from aquaculture serve as the main input for developing the organization logic of floating settlements.

Acquired Knowledge / Inputs Feedback Main Drivers for Settlement Logic Investigation Layers of Inputs Objective

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4.1.1

BASIC UNIT RESEARCH

3m

3m

3m

Fig.4.1.1 -1 Basic structural unit A 3m by 3m by 3m cube is the basic structural unit based on the result of water flow reduction experiment.

3m x 3m x 3m Component Based on the experiments of principles and parameters in the previous chapter, the conclusion has informed the reduction performance. The dimension 3m x 3m x 3m will be the basic component of the wave reduction unit. The dissertation team attempts to modify the density and porosity properties of the component to meet three objectives. First, it needs to able to manipulate material density, for the purpose of different applications or environmental conditions. Second, the rigidity capability of material performance to absorb the forces of waves that pass through and around it. Third, it needs to float on the sea.

Material

Aluminium pure

weight (kN/mm3)

Beech

not the focus at this stage. The design team is looking

elasticity strength for material that obtains a low-density characteristic that can float and with capability absorb and reduce (kN/mm3) (N/mm2) Material wave forces. The features of elasticity capability and

27

the ultimate strength limitation are the two features that must be considered in the material performances. However, lacking the physical test to prove the possibility is one of the research limitations. Therefore, as far as the research has studied, a composite material will be the appropriate choice for the wave reduction system (Cobb, F. 2008).

69

<58

78

180

520-720

7.4

10

48

The aggregation scenario has been tested by using different density modules. The potential is to achieve varied porosity performances in for example on the 12 meters long component (Fig.4.1.1-2). There are four

134

modules in different porosity have been generated. In the case of the unpredicted sea conditions or wave structure, to introduce the composite differentiation material becomes the target in this experiment.

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

Concrete

PVC


3x3(m)Modules

Protential Unit Variation

Primitive

Module 1 Volume: 2.45 m2 Porosity: 92%

Module 2 Volume: 4.08 m2 Porosity: 87%

12m

Module 3 Volume: 10.05 m2 Porosity: 69%

Module 4 Volume: 16.05 m2 Porosity: 50%

Fig. 4.1.1. -2 .A Module aggregation By using different porosity, modules to achieve a 12meter structural component. The test was an idea for underwater wave reduction structure.

Material Property

Material

Aluminium pure

weight (kN/mm3)

elasticity (kN/mm3)

strength (N/mm2)

Material

weight (kN/mm3)

elasticity (kN/mm3)

strenghth (N/mm2)

Concrete

24

17-31

10-70

15

10

100

27

69

<58

78

180

520-720

Beech

7.4

10

48

PVC

13

2.4-3.0

48

Poplar

4.5

7

20

Rubber

9.1

0.1

7-20

4.0

Fig. 4.1.1 -3 Material performance The study of diversity material performances informed the design team looks for the composite material scenario.

DESIGN DEVELOPMENT

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4.1.2

GENERATIVE FORM FINDING

Z 30m

m

30

3m

3m

Y

3m

X

Fig. 4.1.2 -1 By aggregating a hundred basic units into a regional platform, which were considering the size of current

3m One Unit

Multiple -Units

30mx30m Platform Module The 3x3x3 meter unit can be aggregated into threedimensions to form the intended wave reduction system unit. First a 30m by 30 m layer is formed. And subsequently layers of more 3x3x3 units are added in response to the bathymetry and wave structure. and understand the interaction between each unit, the design team introduced cellar automata logic into the form generation. By choosing the number of neighbors to ‘survive’ or ‘discard’ surplus cell, the following units on the lower level are getting less, which decreases from the initial start state of 30m by 30m platform level. The purpose of using the gradual reduction strategy is considering the generated form’s relation to structural performance and floating stability that when encountering waves For those reasons, the using of CA

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was helping to get the optimized individual while taking into account the relationship between basic units and environmental scenario (Weisstein, E. W. 2002). According to a set of rules based on the states of neighboring cells, the rule is applied iteratively to achieve the target. There are nine cells in a principle grid that has been introduced to the range of effect area. The number of surrounding cells will decide the conditions of the center cell after calculating. There are three results, dead, survival, and rebirth. By each iteration, the new generation will move to next deeper level which means the previous level is the base for the following level. By this way, the form evolves into a pyramid shape or with some peaks underneath. Also, the number of growth layers can also be controlled, therefore can be adjusted for appropriate design requirements.


Cellar automata algorithm logic

effect area

Type 1

dead

neighbors

0

1

2

3

7

Type 2

survival

neighbors

4

5

6

8 rebirth

Type 3 neighbors

Fig. 4.1.2 -2 Aggregation Logic - The strategy of using cellar automata algorithm was considering the interaction between each cell. Therefore, the overall form evolved from the decision of neighbor cells.

7

Morphology

Primitive

m

30m

Direction of Growth

1

Start State

30

12m Fig. 4.1.2 -3 Aggregation Process - The lower level was generated from the upper level. The aim was to achieve a balanced geometry and dampen the wave structure.

2

3

Growth Layers

m

30

30m

depth Wavelength (L)

4 D= L/2

Seabed

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4.1.2

GENERATIVE FORM FINDING

Fig. 4.1.2 -4 criteria that have been tested; each criterion has its weight for analysis.

1.Total Volume

2.Total Surface Area

3.Structural Deformation

Form Evaluation Criteria The concept of wave interaction with floating breakwaters constitutes a multidisciplinary problem, where a combination of fluid mechanics, the dynamic behavior of mechanical systems, and the vibration theory (Elchahal, G, 2009). The design team was looking for the performance of the reduction system that is integrates between the fluid and rigid body. Simplifying the complexity hydrological effects in the study. Three criteria were introduced to facilitate evaluation of generated forms: total volume, total surface, and structural deformation. These criteria can be weighted depending on the priority and context application. First, Total Volume - concerns the total mass, and density of the wave reduction unit. The target can either using the least amount of material possible. Can either and with minimum weight while also taking into amount of volume to gain more mass for applications in stronger wave conditions. In terms of buoyancy a geometry result without considering the implications 138

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

of the geometry to the floating ability and the interaction performance between structural and wave. Second, the Surface Area - relates to the amount of surface area in contact with the fluid. Is related to generating friction. By increasing the amount of surface area, more of the wave structure is obstructed. Meanwhile considering the diversity of wave directions that the perpendicular sides of the reduction system will be introduced to increase. Third, the Structural Deformation value. The test assumed the width of unit equal to the wavelength where forces are directly at the edges of the structure. This is known as the structure critical condition for floating breakwaters. To simulate this deformation, the force points has been set on the four point of the edges.


1.Volume Mass

Gravity Buoyancy = weight of displaced fluid Volume relate to mass Number of struts Void space for the wave transmission

Buoyancy

2.Surface Surface area correlate friction multi-wave directions Increase surface area on sides CFD analysis cu

nt

re ur

rre

nt

c

3.Deformation

Width of unit = Length of wave

Wunit = Lwave

Simplify the force of wave in 4 edges Deformation relate to rigidty FEA analysis

F F

F

Fig. 4.1.2 -5

F

Tools and Methods - By using different tools and methods to test the same algorithm and analyzed in one loop.

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4.1.2

GENERATIVE FORM FINDING Index of Individuals G1

GA Settings: Population data:

G1.1 G1.2 G1.3 G1.4 G1.5 G1.6

Poulation size: 50 Generations: 40 Breeding strategy Exclusive selection Elitism: 0.5 Crossover rate: 0.8 Kill strategy: none Mutation strategy: Mutation probability: 0.1 Mutation rate: 0.5

Fig. 4.1.2 -6 Generated Individuals Data for Comparison and Evaluation - There are four generations which show comparison those four generations, the optimized evolution process can be found in the data.

G14 G14.1 G14.2 G14.3 G14.4 G14.5 G14.6 G20 G20.1 G20.2 G20.3 G20.4 G20.5 G20.6 G40 G40.1 G40.2 G40.3 G40.4 G40.5 G40.6

Ranking Index Volume (m3) Tot.Surf. (m2) Deformation Tot.Fitness Ranking 20% 20% 60% 1 4644 4374 0.079 0.6254 G1.4 2 5670 4878 0.101 0.5974 G1.1 3 4806 4752 0.093 0.6173 G1.3 4 4104 3708 0.076 0.6298 G1.5 5 4131 3744 0.102 0.6142 G1.6 6 5643 4770 0.095 0.6007 G1.2

0.63 0.625 0.617 0.614 0.6 0.59

Ranking Index Volume (m3) Tot.Surf. (m2) Deformation Tot.Fitness Ranking 20% 20% 60% 1 3375 3384 0.055 0.6513 G14.2 2 3483 3582 0.044 0.6588 G14.1 3 3834 3798 0.054 0.6492 G14.5 3888 3798 0.053 0.6488 G14.6 4 2997 2880 0.051 0.6514 G14.3 5 3699 3870 0.057 0.6507 G14.4 6

0.658 0.651 0.651 0.65 0.649 0.648

Ranking Index Volume (m3) Tot.Surf. (m2) Deformation Tot.Fitness Ranking 20% 20% 60% 1 3726 3618 0.048 0.6524 G20.6 2 3780 3744 0.054 0.6495 G20.1 3 4185 4032 0.057 0.6436 G20.2 4 3888 3798 0.053 0.6488 G20.4 5 4077 3942 0.056 0.6452 G20.5 6 3483 3582 0.044 0.6588 G20.3

0.658 0.652 0.649 0.648 Mean value: 0.649 0.645 St.Dev: 0.0053 0.643 Fittest individual: 0.658

Volume (m3) Tot.Surf. (m2) Deformation Tot.Fitness Ranking Ranking Index 20% 20% 60% 1 3591 3510 0.044 0.6558 G40.3 2 3861 3744 0.045 0.6534 G40.4 3 3186 3168 0.034 0.6637 G40.1 4 3348 3474 0.041 0.6615 G40.5 5 3807 4050 0.05 0.6550 G40.2 6 4077 3798 0.044 0.6507 G40.6

0.663 0.661 0.655 0.655 0.653 0.65

Mean value: 0.612 St.Dev: 0.015 Fittest individual:0.63

Mean value: 0.651 St.Dev: 0.0035 Fittest individual: 0.658

Mean value: 0.656 St.Dev: 0.0049 Fittest individual: 0.663

Optimization Results Forms were generated and evaluated by the Genetic Algorithm, based on the value weight applied to each is given to forms that have less deformation (60%). 40 generations were run, stopped and re-run in certain generations to observe results (i.e. Gen. 1-4, 14, and

the results cannot be said as the â&#x20AC;&#x2DC;bestâ&#x20AC;&#x2122; morphology. It is due to the diversity environmental conditions in the sea area, the limitation for the function of reduction system has to be set clearly from the start in order to identify which forms are more appropriate for which applications. Exact values such as target volume, surface area or deformation threshold, has not been

generation were chosen for comparison. It can be seen limitations of the form generation.

Fig. 4.1.2 -7 (Opposite) The layout of six ranked individuals that are considered

140

starts from 0.63 to 0.663 within 40 generations which means it has approached the optimized morphology. However, the value of standard deviation and mean were varied and nearly similar. Although the latest generation has bred low deformation and small volume individuals

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015


Ranking

1

2

G1.4

G1.1

3

4

5

6

G1.5

G1.6

G1

Total Volume (m3) : 4104 Surface Area (m2) : 3708 Deformation (m) : 0.076

Total Volume (m3) : 4644 Surface Area (m2) : 4374 Deformation (m) : 0.079

G1.3 Total Volume (m3) : 4806 Surface Area (m2) : 4752 Deformation (m) : 0.093

Total Volume (m3) : 4131 Surface Area (m2) : 3744 Deformation (m) : 0.102

Total Volume (m3) : 5643 Surface Area (m2) : 4770 Deformation (m) : 0.095

G1.2 Total Volume (m3) : 5670 Surface Area (m2) : 4878 Deformation (m) : 0.101

G14 G14.2 Total Volume (m3) : 3483 Surface Area (m2) : 3582 Deformation (m) : 0.044

G14.1 Total Volume (m3) : 3375 Surface Area (m2) : 3384 Deformation (m) : 0.055

G14.5 Total Volume (m3) : 2997 Surface Area (m2) : 2880 0.051 Deformation (m) :

G14.6 Total Volume (m3) : 3834 Surface Area (m2) : 3798 Deformation (m) : 0.054

G14.4 Total Volume (m3) : 3375 Surface Area (m2) : 3384 Deformation (m) : 0.055

G14.3 Total Volume (m3) : 3699 Surface Area (m2) : 3870 Deformation (m) : 0.057

G20 G20.6 Total Volume (m3) : 3483 Surface Area (m2) : 3582 Deformation (m) : 0.044

G20.1 Total Volume (m3) : 3726 Surface Area (m2) : 3618 Deformation (m) : 0.048

G20.2 Total Volume (m3) : 3780 Surface Area (m2) : 3744 Deformation (m) : 0.054

G20.4 Total Volume (m3) : 3888 Surface Area (m2) : 3798 Deformation (m) : 0.053

G20.5 Total Volume (m3) : 4077 Surface Area (m2) : 3942 Deformation (m) : 0.056

G20.3 Total Volume (m3) : 4185 Surface Area (m2) : 4032 Deformation (m) : 0.057

G40 G40.3 Total Volume (m3) : 3186 Surface Area (m2) : 3168 Deformation (m) : 0.034

G40.4 Total Volume (m3) : 3348 Surface Area (m2) : 3474 Deformation (m) : 0.041

G40.1 Total Volume (m3) : 3591 Surface Area (m2) : 3510 Deformation (m) : 0.044

G40.5 Total Volume (m3) : 3861 Surface Area (m2) : 3744 Deformation (m) : 0.045

G40.2 Total Volume (m3) : 4077 Surface Area (m2) : 3798 Deformation (m) : 0.044

4.0

G40.6

Total Volume (m3) : 3807 Surface Area (m2) : 4050 Deformation (m) : 0.050

DESIGN DEVELOPMENT

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4.1.3

ADAPTIVE WAVE REDUCTION UNIT MORPHOLOGY

Wavelength (L)

Submerged Area (d)

Fig. 4.1.3 -1 The interaction relationship between the wave reduction individual and wave. Importance of Width of Structure and Depth to obstruct wave structure

Depth of Wave Structure = L/2 Wave Base

Water Depth

Sea Bed

Fig. 4.1.3 -2 (Opposite) Different Individuals have different properties that can be applied depending on the requirements at the context and the unitâ&#x20AC;&#x2122;s performance characteristics where it is needed.

Select Morphologies for Comparison The selection process was based on the performance values that can be applied in different sea conditions. performance in distinct aspects that are the ambitions the design team aiming for reaching. For the concern of varied sea conditions, they will be placed in a particular In generation 40.3, the individual has achieved the underwater surface area that dampen the wave force. Therefore, the location of this individual will be placed behind the wave reduction platforms where has the most population activities. The generation 1.2, the individual with the highest deformation value and most surface area will be placed offshore to withstand the high wave and strong wind 142

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

As for the smallest individual, generation 14.5, the location will placed near shore where has the least impacts that from wave and wind. The GA results have informed the design team a variety of choices that can apply in any sea scenario. That has become the regional platform for the aggregation towards to the global settlement.


G40.3

G40.5

G14.5

G1.2

Mophology data:

Mophology data:

Mophology data:

Mophology data:

Dimensions: length 30m, width 30m System Depth: 13m 3186 Total Volume (m3) : 3168 Surface Area (m2) : 0.034 Average Deformation (m) :

Dimensions: length 30m, width 30m System Depth: 16m 3807 Total Volume (m3) : 4050 Surface Area (m2) : 0.050 Average Deformation (m) :

Dimensions: length 30m, width 30m System Depth: 10m Total Volume (m3) : 2997 Surface Area (m2) : 2880 Average Deformation (m) : 0.051

Dimensions: length 30m, width 30m System Depth: 16m Total Volume (m3) : 5670 Surface Area (m2) : 4878 Average Deformation (m) : 0101

Fitness:

Fitness:

Fitness:

Fitness:

01. Total Vo. / Target Vo.

01. Total Vo. / Target Vo.

01. Total Vo. / Target Vo.

02. Underwater surf./ total. 03. Target deformation

Performance:

30% 72% 97%

02. Underwater surf./ total. 03. Target deformation

Vo.(20%)

Sur.(20%)

Section information: structure buoy

35% 77% 95%

02. Underwater surf./ total. 03. Target deformation

Vo.(20%)

Def.(60%)

Sur.(20%)

Section information:

01. Total Vo. / Target Vo.

27%

02. Underwater surf./ total.

68%

03. Target deformation

95%

Vo.(20%)

Def.(60%)

Sur.(20%)

53% 81% 90%

Vo.(20%)

Def.(60%)

Sur.(20%)

Section information:

Def.(60%)

Section information:

Pros: Fittest individual Most-rigid structure

Pros: High surface area High rigidity structure

Pros: Min. surface area Min. total mass

Pros: Max. surface area Less-rigid structure

Cons: Less-flexibility

Cons:

Cons: Less capability to dampen wave due to the shortest depth

Cons:

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4.1.3

ADAPTIVE WAVE REDUCTION UNIT MORPHOLOGY

Fig. 4.1.3 -3 3D Printed models of the wave reduction units.

Conclusion Through series of experiments, the potential of developing an adaptive wave reduction system was explored. A morphology based system that can be applied to different contexts and wave scenarios. For example, the results of experiments show that generation 40 can adapt more severe hydrological conditions with the average 0.044 structural deformation value. That advise the design team can apply morphology to different sea condition zones. In particular, variation appears to lessen the total volume and surface area to achieve the low structural deformation value. The selection adaptable individuals are from generation 1 to 40 for applying in different scenarios.

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Although the design team realized the important to understand the correct relationship between optimization and diversity, the lack of targets for the when dealing with a large â&#x20AC;&#x2DC;populationâ&#x20AC;&#x2122; of morphologies. hydrological process calculations has not yet been integrated to the evolutionary process. Therefore, the CA logic for the relationship between each neighbor and outer forces is still not clear. Furthermore, without identifying the desired targets, evolutionary results will continually optimize towards minimized value, which is not entirely the desired results.


4.1.4 to 4.1.6 WAVE REDUCTION SYSTEM DESIGN POTENTIAL The following sections discuss the design, functional considerations and potential of the wave reduction system based on the available generated morphology design.

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4.1.4

UNIT CLUSTERING & MOORING STRATEGIES

Single Unit Mooring Principle

Wave Reduction Unit Motions High Tide / Extreme Surge

30m

Normal Sea Level Low Tide

Wave Direction

30m

Plan

Heave Vertical movement caused by tidal changes, wave oscillation motion, and buoancy forces.

Securing the Unit on Sea Floor

Roll Forward rotational motion often caused by waves with large height, long wavelengths and periods

Sway Horizontal movement caused by waves with shorter periods

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Anchors as part of the mooring system are important to secure the chain lines and wave reduction units in place and preventing it to be dragged by hydrodynamic forces. Different anchor types can be considered depending on the location and sea floor conditions. The system design considers the stockless anchor for ease of application and removal. The anchor is then connected to the wave reduction unit by steel chains in a catenary position. The purpose of the catenary chain type mooring system was selected to allow the wave reduction unit enough freedom of movement especially to accommodate the tidal range and extreme storm tide conditions, also as shock absorber between the wave breaker unit and the anchor. The chain lying on the sea floor transfers load horizontally preventing the anchor to breakout. The disadvantage of using catenary type is that the area needed for application is wider, compared to taut type. Which may be an issue considering if multiple units or platforms are placed on a constrained site. The length and flexibility of the chain system only slightly affects the wave reduction performance of the unit given that the breakwater has a very large mass and weight (including weight of the chains), making it hard for the waves to oscillate the whole structure. (Elchahal et.al, 2009). The movement of the unit also can help dampen the wave energy.


Wave Direction 6m High Tide

Extreme Storm Surge Storm Surge Normal Water Level Storm Surge on Low Tide

Normal Sea Level

5m

Tidal Range

Low Tide

10m-35m B

Range of Depth Application

FDrag

FDrag A

Anchor

Sea Floor

Length of Chain on Floor

Anchor

Section A-A’ Drag Anchor Embedment

Anchor

Steel Chains

A

FDrag

1

Sea Floor FDrag

2 FDrag

Fig. 4.1.4 -1

B

A) Two Types of Drag Anchor B) Steel Chains

3

Photos From: www.vryhof.com; U.S. Navy photo by Photographer’s Mate 2nd Class Johnnie R. Robbins. [Public domain], via Wikimedia Commons; www.red-anchor.co.uk

FDrag

Buried Fluke

4

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4.1.4

UNIT CLUSTERING & MOORING STRATEGIES

Multiple -Units

Fig. 4.1.4 -2

Single -Unit

Clustering of Wave Reduction Units form the larger Wave Reduction Platform

Clustering Multiple Floating Wave Reduction Units increases dimensions

Wave Reduction Platform / Floating Public Platform

Combining Multiple Units and Mooring Strategies Combining or clustering multiple wave reduction units to form a wave reduction platform (or potentially a public platform) is essential to adapt to larger wave conditions, such as longer wavelength, and higher waves. By aggregating units into platform, the overall width, mass and weight is increased. It will be harder for the wave to induce motions heave, sway and roll on the platform. The effectiveness to reduce wave height will vary according to the rigidity of the whole platform. To be constructed by combining 30mx30m units, the connection between units becomes a concern to enable it to function as one larger wave reduction platform.

Fig. 4.1.4 -3 Opposite - show the two ways to consider the mooring of the wave reduction platforms

148

Rigidity is an important characteristic for effective reduction of wave transmission. At the scale of the platform, this rigidity is achieved by how much freedom each unit is allowed to move in relation to its neighboring unit. For this dissertation, the connection between two units will not be part of the research scope, but in design is assumed to have different degrees of freedom to accommodate variation in flexibility requirements.

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

These requirements are dependent yet again to the varying conditions of the wave scenario. To secure the platform, it utilities similar principles for the mooring a single unit. And for platforms, two mooring system approaches can be used. One, is to individually anchor all units to the sea floor, and another, strategically connect edges of some units to the sea floor and introduce a connecting element. The advantage of the latter is having less mooring lines, potentially making it more economical, easier to rearrange the units, and provides less obstacle for boats moving around or docking on the platform. Its potential strength, where joints are located it becomes a point of weakness of the structure, thus also affecting wave In the study of E.Pena et.al (2011), they recommend that all floating breakwater units be anchored to the sea


Tide

60m

Roll

ave

All Units Moored

60m

Sway 60m

Roll Single Unit Mooring Principle

60m

30m

60m

Wave Direction

30m

90m

Introducing Connections Plan and Mooring of Platform

way

Plan

Wave Reduction Unit Motions High Tide / Extreme Surge

60m

Normal Sea Level

90m

Low Tide 60m

Aâ&#x20AC;&#x2122;

Plan Heave Tide / Extreme Surge

mal Sea Level

60m

Tide

Plan

90m

60m

120m

90m

ave

60m

Roll

Plan

60m

Plan

A

60m

Roll Sway

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60m 90m

4.1.4

UNIT CLUSTERING & MOORING STRATEGIES 120m

Plan

Plan

60m

A

Aâ&#x20AC;&#x2122;

90m

90m

120m

Plan

Plan

A

90m

floor to lessen the forces absorbed on the connections between two units. The wave reduction platform can perform wave attenuation in various wave conditions. However, it is important to understand the relationship of short and long wavelengths with the platformâ&#x20AC;&#x2122;s structure. A platform is composed of multiple units clustered together to function as one single wave reduction unit. At this scale what becomes more critical is not the deformation of each individual unit, but the capacity of connections of unit-unit to absorb extreme stress, and allow rotational movement.

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ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

Having longer width, and more connections affects the rigidity of the system to act as one unit. But not all platforms need to be very rigid, as movement also helps dampen or dissipate wave energy, especially if focus is for wave attenuation. But as the opportunity for the platform to be habitable, rigidity will be an important consideration. Therefore, the strategies of anchorage and mooring lines can be further developed and studied giving more emphasis on either connection design. However, for the succeeding experiments of this anchorage for the wave reduction unit to perform in context.


High Tide

Storm Surge on Low Tide

Normal Sea Level

5m

Tidal Range

Low Tide

10m-20m B

Range of Depth Application

FDrag

FDrag A

Anchor

Length of Chain on Floor

Sea Floor

Anchor

Section A-A’ Short Wavelength (L) Wave Direction

6m

Extreme Storm Surge Storm Surge Normal Water Level Storm Surge on Low Tide

5m

Tidal Range

15-35m Range of Depth Application Anchor

Anchor Sea Floor

Section A-A’ Long Wavelength (L)

Wave Direction

6m

Extreme Storm Surge Storm Surge Normal Water Level Storm Surge on Low Tide

5m

Tidal Range

15m-35m Range of Depth Application Anchor

Anchor Sea Floor

Section A-A’ Fig. 4.1.4 -4 Illustration showing the rotational forces that interact with the connection in between two wave reduction units when joined together. Response varies depending on wavelength.

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4.1.5

POTENTIAL FLOATING PUBLIC PLATFORM

Program Morphologies

Clustered Floating Wave Reduction Platform

Floating Public Platform

90 m

90 m

MAIN MARKET PLATFORM

152

60 m TOURIST PLATFORM

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

90 m

60 m

60 m

LOCAL PUBLIC PLATFORM


People

Supplies and Materials

Built Structure

Reserve Buoyancy

Draft = 12m

Water Level

Depth of Unit 14m

Volume x Mass Density = Allowable Load

Freeboard 2m

Live Load < Allowable Load

Built-structures Loading / Unloading Cargo Water Level

CG CG

Overturning moment

Public Platform Typologies Clustering of wave reduction units together can produce a larger platform. The primary purpose of this is to deal with larger waves and wavelengths for off-shore wave reduction. As waves are further reduced inshore, the platforms present an opportunity to be habitable. The for a community oriented settlement organization. The Main Market platform - where major commercial transactions, and community wide activities take place; Tourism Platform - accommodating visitors for leisure and learning; and Local Community platform, where

most aquaculture process, production are done. The logic of the built morphology on top of the platform will not be the focus at this stage, and will be further developed in another phase of the dissertation. These typologies will serve as key points in the development of the settlement organization logic (Section 4.2.) . This opportunity opens up new concerns particularly the rigidity, stability and buoyancy of the platform.

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4.1.5

POTENTIAL FLOATING PUBLIC PLATFORM

Object Stable

Object Floats

Wobject

Wobject

Water Level

Water Level CG c

CG

Volume of fluid displaced

c

Fb

Fb

Object Unstable

Object Sinks Wobject

Fig. 4.1.5 -1 Archimedes Principle of Buoyancy; and Stability of a floating object

CG c

Volume of fluid displaced

Restoring moment

Wobject

Water Level Water Level

CG

Volume of fluid displaced

Volume of fluid displaced

c

Fb

Fb

Overturning moment Wobject

Stability of Floating Platform The stability of the floating platform is very important when considering the daily aquaculture activities. Two types of loading constantly affect the platform, static and dynamic. Static or dead loads include the platform’s own weight, and built structures, and material and products inventory. Dynamic or live loads are villagers in numerous large boxes for market supply; prepare or dock and load or unload people. All of these activities are done on a floating platform, and contributes to the shifting of loads, and center of gravity of the platform. and depth to counter moment forces caused by shifting of weight to one side of the platform. Although not yet calculated at this stage of the research, the built structure height will be limited by the capacity or design of the floating platform based on the buoyancy principles. 154

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

Fb

Weight of Object

CG

Object’s Center of Gravity

c

Centroid of volume of displaced fluid / Center of buoancy Buoancy Force

A simple strategy would be to design the platform with a loading limit, or apply strategy similar to the principles of a ship or submarine’s ballast system. There is a potential to embed a responsive system (of pumps and the buoyancy units at a required time. Different unit morphology require different number of chambers and air tanks to address required volume and lessening of density for buoyancy. This strategy is yet to be explored. Also the relationship of the morphology to the number and location of buoyancy units or chambers has not been investigated yet. The stability of the platforms, its reserve buoyancy, and capacity for loading is more are added, to address limitations or capacity.


Activity Concerned

Loading and unloading of supplies, materials and aquaculture products affecting the stability of system Strategy for Restoring Stability

Large quantities of aquaculture products, built structure, and people add weight to the system affecting its buoancy Strategy for Restoring Buoyancy

Wobject

Wobject

Water Level

CG

CG

c

c

Fb

Fb

Loading / Unloading Cargo

Wobject

Wobject Water Level CG

c

CG

c Fig. 4.1.5 -2

Fb

Wobject

Daily activities concerned that affect stability and buoyancy of the floating units or platforms. Potential strategy to restore equilibrium is by embedding a responsive system similar to ballasts of ships or submarines.

Fb

Wobject Water Level

CG

CG

c

Float / Empty Air Chamber Structure / Water Filled Chamber

Fb

Structure / Weight

Fb

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4.1.6

WAVE REDUCTION SYSTEM CONTEXT ADAPTATION 0

-10

-30

(m)

Wave Reduction Units

Wave Reduction Platforms

Less Deformation, More Rigid, less volume

SITE

Context Map G14.34 3807 4050 0.050

Total Volume (m3) : 2997 Surface Area (m2) : 2880 Average Deformation (m) : 0.051 Vo.

G40.32

Adaptable Site Application Parallel to the context abstraction and the strategies tested in Chapter 3 - Wave reduction experiments, the performance of each wave reduction unit and its capability to aggregate to form a platform allows it to adapt to different conditions, therefore allowing variation in site application. There need not be only one type of design to be selected

3186 Total Volume (m3) : 3168 Surface Area (m2) : Average Deformation (m) : 0.034 Vo.

G40.52 3807 Total Volume (m3) : 4050 Surface Area (m2) : Average Deformation (m) : 0.050 Vo.

corresponding performance characteristics of a set of units or platforms, an appropriate morphology can be scenario. These units or platforms can then be placed at the site in different arrangements producing patterns. As these wave reduction platforms are positioned, the reduction of wave height is relevant to the platformsâ&#x20AC;&#x2122; position to one another, thereby it will produce variation in wave height reduction throughout the site. The pattern will be optimized to achieve the highest area coverage of safety threshold that could accommodate aquaculture and floating settlements. Pattern changes and unit clustering are tested in Chap 3 and results are utilized in Chapter 4 used as one of main strategic driver for the settlement logic organization experiments and design.

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G1.11 Total Volume (m3) : 6075 Surface Area (m2) : 5400 Average Deformation (m) : 0.104 Vo.

Larger Volume and Overall Surface Area More mass, weight , more surface area for water friction

Select, emergent platform morphology types based on simple clustering rules on site experiment and relationship to wavelength and water depth


Platform Properties Shorter Platform Width to perform better in shorter wavelength conditions

Average Platform Depth concerning platform stability, and depth of water

900m

Near-Shore Shorter Wave Length 20m-30m

More Rigid for shorter wave periods and potential as floating public platform

Zone 5 (Lowest Risk)

Shallower Water 10m-15m Wave Height 2m-4m - Settlement Capacity

Zone 4

Zone 3

Zone 2

Offshore Platform Properties Larger Platform Width to perform better in longer wavelength conditions, also to increase mass and weight

Longer Wave Legnth 120m-160m Less Rigid Allows for wave dampening action

Zone 1 (Highest Risk)

Deeper Water >30m Wave Height 6m - Destructive

Larger Platform Depth to further obstruct the wave structure also to increase mass and weight

Direction of Wave Approach

Zone 1

Zone 2

Zone 3

N

Zone 4

Zone 5

Off-shore

Near-Shore

Section (not to scale) 4.0

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4.2 FLOATING SETTLEMENT ORGANIZATION

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4.2.

SETTLEMENT ORGANIZATION INVESTIGATION OVERVIEW

( Network ) Supply and Market Distribution

( Wave Reduction System ) reduction performance

( Zoning and Program ) distribution Low-Risk Areas Aquaculture product regions Local and Tourist Integration

( Settlement aggregation ) and Density distribution Settlement growth and population

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(

Adaptive floating ) Settlements Organized logic based on aquaculture activities

Experiment Strategies The floating settlement organization design strategies are based on the platform pattern result of the wave reduction system. The results inform the other design organization drivers such as the network, zoning and program, and density distribution. The platform positions are evaluated with regards to the aquaculture activities on the network, zoning and program distribution as the rules for organizing the settlements. In the next sections, the design research is developed to evaluate the public platforms by the weighted graph. construct the graph and to analyze the algorithm. Only platforms within Low risk zones Zone 2-4 (see previous public programs. In the later stages of the research, a more complex network based on the multiple centers has been introduced after the initial network experiments, in order to meet the adaptive conditions of aquaculture settlements activities.

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Network logic

4.2.1

NETWORK

Goods distribution

Network logic

Network logic

Goods distribution

Goods distribution

Legend Coastal port

Resource distribution within public platform network

Network logic

Network logic

Goods distribution

Goods distribution

Resource distribution secluded from public platform network

Fisheries products distribution within the public platform network

Network logic Goods distribution

Main market

Fisheries products secluded from the public platform network

Local public platform

Tourist public platform

Distributed resources include : Food Water Medicine Fish raft building material Fuel Step depths >5

0

Aquaculture raft

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Why Develop the Network First? Dispersed settlements are considered as the extended metabolic system, from which cities start emerging, condensing into nuclei within the integrated arrays and information, and increase in social and cultural complexity. (Weinstock, 2010 ) In order to create a new community, principles of the flows based on its topographies and ecological properties should be studied. The implication of flows and networks are opposite sides of the same coin, they rely on each other and need to how people represent and simulate citesâ&#x20AC;&#x2122; connections and intersections(Batty, 2013). By exploring different type of networks, corresponding flows between locations will be examined and provide at the same time. The form and network of a floating community is different from a regular city on land, however, still informed by the material energy and information flows. There should be the mathematical similarities in metabolic distribution networks of living forms and the culturally produced

networks for the distribution for the information and energy (Weinstock, 2010). Considering the wave impact pattern of the community, a set of platforms have been positioned in the proper places with reference to each activities. Energy and activities flows have been studied. The network strategy it is currently the main activity on the site. However, another activity - Tourism is introduced to the site in order to balance the socio-economic aspects of the community These activities are situated on and surrounding the public platforms. The hierarchy of the platforms is resources distribution are two main issues on the site either for aquaculture, local villagers and tourist. By exploring the flows of the distribution, hierarchy, centrality, accessibility of each platform will be evaluated. Different density of settlement growth will be tested to understand the threshold of stability.

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4.2.1

NETWORK Land-Based` Village 0

-10

-30

2

(m)

Village 1

900m Near-Shore

SITE

Village 2

Village 3

Land-Based` Village

2100m

Context Map

Land-Based` Village

1

3

Off-Shore

Wave Direction

The Network Method Computer Science, Graph and Urban Networks Graph diagram has been widely used in computer science and is the visual representation of the data structure. With a set of nodes and edges, the relations of nodes can be clearly illustrated. Multiple properties can be assigned to the edges to illustrate the relations, such as the distance, flow strength and direction. There are several algorithms that are commonly used to help tackle the data structure issue. For instance, binary search and balanced search trees are used for achieving the proper

Centrality , Accessibility , and Hierarchy in Spatial Networks of different network strategies can be evaluated in a will be examined and compared, for implementing proper networks based on its context. Centrality of the nodes within the networks is one of the main values that routes. It is the mathematical representation of flows for SNA (Social Network Analysis).

164

mathematical relation in resource flow based network and computer science data structure will be explored in the following experiments. With the help of the existing

The accessibility can describe the relation within a network. After the proper boundary condition was set up, the relation to the outside context can be evaluated

networks for comparison. By abstracting the urban network into a pure mathematics structure, hierarchy of locations can be represented as weighted nodes, while flows can be reflected by the directed edges. At the same time, the distance and strength can be illustrated by multiple layers of weighted properties for the edges.

the network, the rest of the nodesâ&#x20AC;&#x2122; relation with another node can be described with hierarchy. It commonly used to represent the spatial depth between two nodes.

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015


0

-10

-30

(m)

Village 1

SITE

Village 3

Village 2

Context Map

5 4 3 2 1

Single pole Network

0

Depths >5

Resource flow has been represented with solid edges, while colors of the nodes show the hierarchy of the step depth from center to the boundary of the site. Contributed by its centrality and hierarchy of the network, it manages to achieve the minimum overall network span. If the edges of the network is converted into the physical form for resource distribution, for example water pipes or utility cables, it turns out to be the most economical strategy. However, the level of hierarchy

Fig 4.2.1 -1 0 Main market Main market location

Depth value mapped on the public platforms for Single pole Network experiments together with the Topological diagram of Depth value shows the location of node. Depth graph illustrates the single pole network results.

the real resource distribution. Additionally, the distance between network center to boundary is the concerned

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4.2.1

THE NETWORK 0

-10

-30

(m)

Village 1 1 SITE

Village 2

Village 3

Context Map 2

3

Fig 4.2.1 -2 Depth value mapped on the public platforms for Multi pole Network A experiments together with the Topological diagram of Depth value shows the location of nodes. Depth graphs illustrate each nodes results of the Multi pole Network A 5 4 3 2 1

0

1

2

3

Multi-pole Network A (Centralized) Based on the site context research, multiple markets

Depths >5

formation of the network was still based on centrality, but utilizes the highest network centers. By introducing multiple poles for the network, the level of spatial flatter structure compared to the single pole network. However, the distance from the boundary to the centers coastal ports and villages outside the boundary.

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0 Main market Main market location


0

-10

-30

(m)

1

Village 1

SITE

Village 3

Village 2

Context Map

2

Fig 4.2.1 - 3

3

Depth value mapped on the public platforms for Multi pole Network B experiments together with the Topological diagram of Depth value shows the location of nodes. Depth graphs illustrate each nodes results of the Multi pole Network B

5 4 3 2 1

0

1

3

2

Muilti-pole Network B (Edges) In order to meet the balance between the accessibility to guide the network centers around the boundary of the site. Without choosing the highest centrality point as the network centers, the overall network span is unable to However, by applying the Dijkstra Algorithm for the path

Depths >5

0 Main market Main market location

accessibility from the centers of the network to the coastal ports and villages are achievable.

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4.2.2

ZONING AND PROGRAM DISTRIBUTION 0

Objectives

-10

-30

(m)

Village 1

and whole-sale distribution 2. Identify zoning for local and tourist 3. Identify public platform location

SITE

Village 2

Village 3

Context Map

Species 1: Zoning for aquaculture settlements

Water velocity 0.4-0.6 m/s

Species 2 Zoning for aquaculture settlements Fig 4.2.2-1 Zoning and Program Distribution Map. Composed of Various layers of design inputs and information

Water velocity 0.6 - 1 m/s

Species 3 Zoning for aquaculture settlements

Water velocity 0.8 - 2 m/s

Tourist area

Wave Direction Off-Shore

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2 1

3

Legend

Differentiated species regions

Fishery product A Fishery product B Fishery product C n

Costal port Regional market Whole-sale connection Closest distance to market Product A public platform Product B public platform Product C public platform

Regional public platforms distances to main markets

R1

Differentiated species regions

R1

With reference to the research and site survey, differentiated species market nodes are required. After R1

platforms with closest proximity to each main markets form the clusters of public platforms to facilitate the needs of aquaculture industry while providing services for locals. The ratio of three different species are based on the market demands, it could be highly adaptive to the economic changes, therefore, the required ratio of the public platforms is achieved by the proper weight of such values. As the ratio of the platforms serving for both local people and aquaculture industry can be controlled and informed by local governments, its arrangement may follow the top-down logic, however, it has the advantage of the highly adaptive aspects of the informal, selforganized arrangement which is flexible when facing with economic changes and varied market demand.

Equal cultivation per species

R2 R3

R2

R2 < R1 < R3

Fig 4.2.2-2 The diagrams illustrate the differentiated species regions.

DIfferentiated cultivation per species

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4.2.2

ZONING AND PROGRAM DISTRIBUTION

Legend

n

Fishery product A Fishery product B Fishery product C Costal port Main market Whole-sale connection Accessibility from coastal ports to tourist platforms Tourism platform location Tourism zone Local zone

Tourism platforms located on closest path connecting markets.

Local zone Tourist zone

Seperation of local and tourism zone.

Tourism Tourism has been a strategy clearly mentioned in the local government documents. It is considered as the long term adaptive strategy for the economic growth and changes. By adjusting the ratio of tourism and aquaculture on the site, the local community will be more flexible when dealing with the environmental changes, market demands, economic changes. To create the route for tourists, three main market centers serve as the main accessibility points for visitors where tourists are transported into site by accessing these

1

3

Seperated locals and tourists accessbility.

two main centers will be found, all platforms on the paths then converted into tourist centers, which form up the tourism zone and a closed circle for tourist route. semi-local platforms, which facilitate services for both locals and tourists. The ratio of tourism and aquaculture therefore it does not change without rearrangements. Thus, the adaptivity of the ratio is considered as longterm strategy. Tourist excursion loop 170

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2


Main market

Local platform: Product 1

Legend Main market

Local platform: Product 2

Local platform : product 1 Local platform : product 2

Local platform: Product 3

Local platform : product 3 Tourist platform Semi - Local platform Tourist zone

Aquaculture regions

Tourist public platform Semi-Local platform: Product 2

The Integration of Local Aquaculture and Tourism

Semi-Local platform: Product 3

As discussed in previous page, three main centers hierarchy of three groups of platforms. By introducing the tourism into site, some of the platforms along the edge of the tourism zone have been converted into tourists center, while some platforms within tourism zone has been converted into semi-local platforms, on which serve both locals and tourists.

Tourist area

Main market

Local platform

By constructing the network and dividing the zones. A clear logic of distributing the programs from network centers to its boundary, from local aquaculture to public tourism area has be presented. Values of the programs and networks will become one of the critical factor that influence the settlement growth.

Tourist public platform Semi-Local platform

Fig 4.2.2-3

Integrated Local and Tourist

The diagrams illustrate the tourist zone formation, accessibility and routes.

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4.2.3

SETTLEMENT AGGREGATION AND DENSITY DISTRIBUTION

Fig 4.2.3 -1 The aggregation of the aquaculture raft at the site

Settlement aggregation logic The arrangement of the public platform is a bottom-up procedure that fully considers the wave impact and the

Low Risk

High Risk Z3 Z2 Z1

and safer public system that could serve locals better. For the settlement growth, the proposal aims for the system that helps the self-organized settlement grows by providing information and guidelines which includes wave impact data, aquaculture market trend, tourism demand and the appropriate density for each area.

Proximity to public platform

By receiving a set of information, each family could make their own decision to pick up a location to settle

Tourist

situation and preferences. Local

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Wave reduction & Safe zone

Local and Tourist zoning


Aquaculture settlement raft

Fish food preparing platform

Semi-tourist settlement raft

Housing unit Aquaculture cage

Aquaculture cage

Tourist area

Fig 4.2.3 -2 30 m

A Aquaculture raft Specie A

Settlements morphologies and aggregation logic

30 m

B Aquaculture raft Specie B

C Aquaculture raft Specie C

D Mixed aquaculture and tourist raft

Public Platform

1 Family / Fish Raft Unit (30mx30m)

Public Platform

Aggregated settlements

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4.2.3

SETTLEMENT AGGREGATION AND DENSITY DISTRIBUTION

Density Distribution Wave impact, proximity to public platform and zoning are three main layers that were overlaid together with a given weight that inform the settlement growth order. Wave impact, the most important factor, determines the accessibility level from its location to the public by the tourism zone. The values are stored within the map. Assuming all the locals are fully informed by the government with values, different types of families based on their own demands to weight the values, the weighted values will be ranked, higher value location

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Aquaculture settlement and aggregation

Safe zone

Low risk zone for settlement growth Fig 4.2.3 -3 The diagrams illustrate layers of settlement logic including the lowest risk zone, proximity to the public platform and the hierarchy of the settlements

Proximity to the public platform

Local zone Tourist zone

Legend Main market Proximity High risk zone Safe zone Aquaculture raft Tourist zone

Hierarchy of settlement growth in Local and Tourism zone

Local zone

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4.2.3

SETTLEMENT AGGREGATION AND DENSITY DISTRIBUTION Aquaculture settlements variable density

Fig 4.2.3 -4 The diagrams illustrate three different densities settlements

100 Families

200 Families

Center Center Market MarketMarket Center 300 Families Species Species A Species A 50%50%A 50% Species Species B Species 20% B 20%B 20%

Density Distribution Conclusion Settlements developed and grew until they were delicately poised close to their critical threshold of stability, and were then extremely sensitive to changes within their environment (Weinstock,2010). The growth of the settlements will reach a threshold for a certain density. The rising density of settlement and the environmental capacity. In order to maintain a sustainable environment, overall density of the settlement should be controlled within a proper range. Binary search Method has been used to approach to the number that maximum family could grow within the site.

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Species Species C Species C 30%30%C 30%

Legend MainMarket market Center Product 1 Species A 50%

50%

Species B 20% Product 2

20%

Species C 30% Product 3

30%


100 Families

200 Families

Fig 4.2.3 -4 The perspectives illustrate three different densities of the settlements

300 Families 4.0

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4.2.4

THE ADAPTIVE FLOATING SETTLEMENT ORGANIZATION Summary of design layers

Adaptive Context Input

Design Control

PlatformArrangment & Wave Reduction

Platform Position

Zoning Local and Tourist Zone & Aquaculture

Network Strategy

Proximity Accessibility to Pulbic Platforms

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Settlement Growth Values to generate tendencies for Family aggregation


Control

Genetic Algorithm Evaluation

Ranking Weight input Ranked Individuals and Output

Wave Pattern High & Low Risk Area (%) Inform

Regional Density Evaluate the Settlement and aquaculture impact to the site

Objectives

Design Outputs

Programs detail distribution and ratio

Overall Span + Max Depth Accessibility

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4.2.4

THE ADAPTIVE FLOATING SETTLEMENT ORGANIZATION Adaptive variable parameters

Zoning area

Public Platform ratio

Local : Tourism

Facilites for species regions

Density

Number of households

community is achieved that is able to adapt to complex socio-environmental changes. This includes the extreme weather, ecological changes, economic changes, and political changes. Three groups of parameters are used to describe the to describe the platforms arrangement and their spatial relations. This part is mainly affected by the wave impact, topography and other environment factors. The second group of parameters are used to control the program distribution and network arrangement. And the third group are parameters that describe the context of the design. For this reason, only the third group of values design condition. several algorithms to adapt to the proper design context. reflected in a long-term time scale, while the second group of parameter reflects the changes in a short to 180

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Species ratio

Number of each species settlement rafts

Semi-tourist raft ratio

Semi-tourist : Aquaculture Settlement rafts Settlement rafts

mid-term time scale. In order to evaluate this adaptive strategy, six scenarios were set-up that describe the types of context changing in a six-year time line. The set of scenarios also illustrate the procedure of how an aquaculture dominant community transforms into a tourism dominant community with the integration of short term and long term transformation. The adaptive variable parameter of long term for these six scenarios is zoning ratio between Local and Tourism which is the result of wave reduction pattern of platforms arrangement. The medium and short term parameters are the density and public platform ratios for separated species. These parameters are adaptable to different situations. The ratio between Semi-tourism and the aquaculture settlement rafts is considered in the third group of all parameters which highly responds to the situation in short term.


Industries/ Activities trend

Aquaculture

Tourism Tourism based settlements

Aquaculture based settlements

Year ( Scenario )

1

2

3

4

5

6

Aquaculture dominant

Species Imbalance

Reorganized Public platform

Early stage transformation

Accepting Tourism

Tourism dominant

Wave reduction pattern 1

Wave reduction pattern 2

Wave reduction pattern 3

Zoning Local : Tourism

Density Settlement type A:B:C Public Platform ratio A : B :C Semi-tourist Settlement ratio Local : Semi-Tourism A+B+C : D

1 specie higher

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4.2.4

THE ADAPTIVE FLOATING SETTLEMENT ORGANIZATION Scenario 1 : Aquaculture dominant Legend CMain

market

Fish AType Species 50% 1 Species 20% 2 Fish BType Species 30% Fish CType

3

Zoning area (% of the whole site) Local (%) Tourist (%)

: 2.3 : 77.7

Public Platform Ratio A:B:C

: 1:3:1

Settlement Ratio A:B:C

: 1:3:1 ( 20,60,20)

Density Number of households

: 100

Locals Vocational Interest Tourism : Aquaculture

: 1:5

Settlement Average Wave height(m) : 2.35 Settlement MaximumWave height(m): 2.87

ratio of aquaculture, and locals are much prefer to work farm distribution, there are equal amount of platforms that serve for three different species. Fish farms are arranged in a low density form. Tourism activity exists but barely contributes to the local economy.

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Scenario 2 : Imbalanced species cultivation Zoning area (% of the whole site) Local (%) Tourist (%)

: 2.3 : 77.7

Public Platform Ratio A:B:C

: 1:3:1

Settlement Ratio A:B:C

: 1:1:1 (100,100,100)

Density Number of households

: 300

Locals Vocational Interest Tourism : Aquaculture

: 1:5

Settlement Average Wave height(m) : 2.22 Settlement MaximumWave height(m) : 3.63

The second scenario shows the species ratio changes demands, thus the ratio of public platform that provide becomes imbalanced. The number of settlement units triple from that of scenario one.

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4.2.4

THE ADAPTIVE FLOATING SETTLEMENT ORGANIZATION Scenario 3 : Reorganized public platform Legend CMain

market

Fish AType Species 50% 1 Species 20% 2 Fish BType Species 30% Fish CType

3

Zoning area (% of the whole site) Local (%) Tourist (%)

: 2.3 : 77.7

Public Platform Ratio A:B:C

: 1:1:1

Settlement Ratio A:B:C

: 1:1:1 ( 200,200,200)

Density Number of households

: 600

Locals Vocational Interest Tourism : Aquaculture

: 1:5

Settlement Average Wave height(m) Settlement MaximumWave height(m)

: 2.35 : 3.93

The third scenario shows that the public platforms adapt Increase in growth of the settlement will aggregate them into the high risk zone, and face risk of high waves. At the same time, the density of the aquaculture generates increasing impacts to the surrounding environments. Thus new strategy needed to provide to adapt to the increasing density.

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Scenario 4 : Early stage transformation towards tourism

Aquaculture with tourist settlements

Zoning area (% of the whole site) Local (%) Tourist (%)

: 22.90 : 57.10

Public Platform Ratio A:B:C

: 1:1:1

Settlement Ratio A:B:C

: 1 : 1.5 :1.2 : 1.5 (149,228,171,225)

Density Number of households

: 630

Locals Vocational Interest Tourism : Aquaculture

: 1:2

Settlement Average Wave height(m) : 2.19 Settlement MaximumWave height(m) : 3.96 In order to introduce new strategy, the platform rearrangement has been introduced in scenario four. It increases the ratio of the tourism zone. The area inside the tourism zone provides a higher density settlement that accommodates more local residences and providing the services for tourists. It gives the potential for further population growth and a new economic type that supports higher population.

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4.2.4

THE ADAPTIVE FLOATING SETTLEMENT ORGANIZATION Scenario 5 : Tourism dominates aquaculture settlements Legend CMain

market

Fish AType Species 50% 1 Species 20% 2 Fish BType Species 30% Fish CType

3

Aquaculture with tourist settlements

Zoning area (% of the whole site) Local (%) Tourist (%)

: 22.90 : 57.10

Public Platform Ratio A:B:C

: 1:1:1

Settlement Ratio A:B:C:D D = Semi-tourist settlement

: 1.4 : 1 :1.9 : 4.6 (119,84,160,387)

Density Number of households

: 750

Locals Vocational Interest Tourism : Aquaculture

: 1:1

Settlement Average Wave height(m) : 2.22 Settlement MaximumWave height(m): 3.73

tourism, and are willing to accommodate the tourists. Settlements start to grow inside the tourism zone and function as the places for both aquaculture and live and work within this area. The tourism starts to grow rapidly.

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Scenario 6 : Highly tourism aquaculture settlements

Aquaculture with tourist settlements

Zoning area (% of the whole site) Local (%) Tourist (%)

: 35.20 : 44.80

Public Platform Ratio A:B:C

: 1:1:1

Settlement Ratio A:B:C:D D = Semi-tourist settlement

: 3.5:1: 3.5 :10.5 (28,8,27,837)

Density Number of households

: 900

Locals Vocational Interest Tourism : Aquaculture

: 1:1

Settlement Average Wave height(m) : 2.21 Settlement MaximumWave height(m): 3.22 The last scenario shows the rearrangement of the platforms caused by increasing demands of tourism. work for tourism. The number of families now reaches to nine hundreds. However, families still grows within a proper wave impact area. It is contributed by the new type of economy and its corresponding settlement type.

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Adaptive Scenarios Conclusion As shown in six scenarios, it shows the potential to create an adaptive community that not only response to the wave impact but also adapt to other changes that the growth of human community need to consider. By the integration of computational techniques, some of the complex topic can be observed deeper. Some of these techniques will be used more frequently during the design procedure. However, this adaptive system has the limitation to illustrate the real site variation, for it is impossible to describe economic, population network with a group of parameters.

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N

Scenario 4

Site Section 0

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30

60

120m

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Storm Situation - High Waves and Heavy Rainfall at the Site.

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5.0 EVALUATION AND FURTHER DEVELOPMENTS

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1.1

CHAPTER SUBTITLE

Conclusion The dissertation is successful in integrating two different strategies namely - the wave reduction system, coupled with the different design levels and considerations for settlement organization. It is possible to develop organization logics for existing and potentially new floating settlements based around these strategies. Also, given different context scenarios and variable social and economic conditions, the organization logic for the settlements is able to adapt to changes by re-arrangement, aggregation, or growth. These adaptive results are achieved by overlaying a hierarchy of considerations and design inputs into multiple algorithms. The values of each layer are evaluated to identify relationships and appropriate selection for settlement growth and aggregation within the abstracted site context. Most of the design and system ambitions are achieved but in a different manner than expected. Anchor points are instead aggregating around floating platforms. Network has been studied in connection to existing ports or villages for resource distribution, but evacuation plan strategy via the network has not yet been investigated. Also, the underwater contour ambition may not be the most applicable design ambition when considering flows and support for migration, or rearrangement is given higher priority. It is recommended to be explored for applicable areas that might encourage Eco-tourism

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or marine ecology revitalization, by which currently there are no opportunities for this at the chosen site context. Some notable aspects: that strategies considered the social logics, particularly the livelihood component â&#x20AC;&#x201C; for this project is the Aquaculture activities. Livelihood is what most traditional settlements are organized around, and in ensuring the people are able to keep or integrate their livelihood, is a critical component in the success of the settlement. By integrating tourism as an alternative or supplemental livelihood can increase adaptive capacity of settlements when faced with vulnerabilities such as extreme weather events that affect their primary source of income and survival. Also, in terms of methodology, due to limitations in available software and facilities, for this research, an attempt is to rather simplify the logic of the simulations. Calculations took into consideration only the parametric relationship of waves and geometry. To simulate the wave conditions for testing wave height reduction, wave equations are taken into consideration and applied to the algorithm. This method also facilitated the integration of strategies and help produce real-time update of results when parameters or variables are changed since it is connected with the algorithm and within one digital and computational interface.


Limitations and Areas for Improvement Floating settlements and sea conditions are very complex systems. Although the study was able to simplify the logics by applying principles and interaction of parameters to address different aspects of the research, it is still not free of limitations and areas of improvement.

Floating Settlement Organization Limitations include: •

The scope of adaptation strategies in this study investigates only infrastructure and communitybased organization growth, and has not looked into its effects on public platform use intensity. (Where one public platform may be overly crowded)

As of this study, the experiments, results and strategies are limited to the abstracted boundaries and the set grid for experiments of 30mx30m cells. Other methods or strategies may arise given a different boundary condition or context.

Evaluation and results of family settlement aggregation and density based on idealized scenario. It is a simulation, but in actual conditions, the results from this dissertation may function as a guidelines for choosing an area to aggregate and settle.

Wave Reduction System Limitations include: •

The wave reduction unit is important but not the priority of the research. It only considers the potential of an adaptive morphology. Material choice, fabrication, integration of mooring system design, and buoyancy and stability calculations are not considered yet in the study. Performance of the system may be greatly influenced by the design and material choice. Boundary conditions and calculations for wave approach by basing it on parameter relationships and results from published experiments. Although, Tsinker (1995) discourages this practice because to the unpredictability and variability of site context conditions, where results of one system may differ from another when tested in a different context. The team is however careful which experiment results to base the calculations and set-up of algorithm from. It must be the closest or similar scale of breakwater, and wave conditions.

Therefore, predicted results only within bounds of published physical breakwater testing results (2.56.0m wave height, 6s-10s wave period). Beyond these scenarios, the system is not able to predict results. Also it does not represent well the actual conditions at site, since experiments only consider one prevailing direction of incoming waves.

Areas for Improvement In studying and analyzing the design layers, although there is a good understanding of what design parameters of each design layer does. The investigation needs to improve in the aspect of iterating and evaluating results, both in wave reduction unit morphology generation and from each settlement organization design layer to further inform the limits or potential of the parameters and in considering the hierarchy of design inputs. For example, in generating patterns of wave reduction systems, what advantages or disadvantages might an equally spaced distribution have compared to a tightly clustered zones of reduction units. This is a layer with heavy implications when network for supply distribution is considered.

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5.2

FURTHER DEVELOPMENTS

Recommendations This dissertation provides a foundational basis for further research and improvement. Two directions can be taken. First, a more in-depth material system study of the Wave reduction system. And secondly, look into developing urbanization strategies for floating settlements.

For Wave Reduction System, majority of the design development presented are strategies and potential solutions. Further developments include:

These two directions no matter how different in scales and considerations might be, are tightly linked and must inform one another when it comes to design. The wave reduction system must be adaptive enough to accommodate various site conditions and settlement demands. The settlement strategies on the other hand to provide safe zones for settlement organization and development.

Material Performance, Fabrication Process recommended to use physical modeling for testing.

Connection between units for aggregation

Mooring System - iteratively design with breakwater morphology

Develop Buoyancy and stability mechanisms or strategies

For floating settlement organization, majority of considerations are different from land based settlement developments. Further developments recommended: • •

Long-term environmental adaptation (effects of water quality and migration or rearrangement options) Network must include other considerations apart include evacuation plan, and re-arrangement

• •

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will navigate in water ways in constrained sites (if not in off-shore open sea areas) Program distribution, and morphology design on public platforms does not consider wave impact yet, and this must be developed. Other considerations for floating settlement functionality include but are not limited to sanitation, fresh water supply, electricity.


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BOOKS E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L.White (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1132

Abbas Hamrang (2014) Materials Science and Engineering. Volume I: Physical Process, Methods, and Model,CRC Press

Gerwick, C. (2002). Construction of marine and offshore structures. CRC Press.

Headland J.R., (1995). Floating breakwaters. In Tsinker G.P. Marine Structures Engineering: specialized applications. Chapman & Hall ed., 367-411

Msangi, S., Kobayashi, M., Batka, M., Vannuccini, S., Dey, M. M., & Anderson, J. L. (2013). Fish to 2030: Prospects for Fisheries and Aquaculture. World Bank Report, (83177-GLB).

Noble, I.R., S. Huq, Y.A. Anokhin, J. Carmin, D. Goudou, F.P. Lansigan, B. Osman-Elasha, and A. Villamizar, 2014: Adaptation needs and options. In: Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Field, C.B., V.R. Barros, D.J. Dokken, K.J. Mach, M.D. Mastrandrea, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L.White (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 833868.

Nuorteva, P., Keskinen, M., & Varis, O. (2010). Water, livelihoods and climate change adaptation in the Tonle Sap Lake area, Cambodia: learning from the past to understand the future. Journal of Water and Climate Change Vol, 1(1), 87-101.

Massel, S. R. (1999). Fluid mechanics for marine ecologists. Springer.

Neumann, Gerhard, and Pierson, Willard J. Jr., (1966), Principles of Physical Oceanography: Englewood Cliffs, N.J., Prentice-Hall, Inc.

Tsinker G.P., (1995). Marine Structures Engineering: specialized applications. Chapman & Hall

Weinstock, M. (2010) The Architecture of Emergence: The Evolution of Form in Nature and Civilization, Wiley

• JOURNALS AND REPORTS •

Cobb, F. (2008). Structural Engineer’s Pocket Book: British Standards Edition. Elsevier.

Creel, L. (2003). Ripple effects: Population and coastal regions (pp. 1-7). Washington, DC: Population Reference Bureau.

Pender, J. (2008). Community-led adaptation in Bangladesh. Forced Migration Review, 31, 54-55.

Daw, T.; Adger, W.N.; Brown, K.; Badjeck, M.-C. 2009. Climate

Porter, J.R., L. Xie, A.J. Challinor, K. Cochrane, S.M. Howden, M.M. Iqbal, D.B. Lobell, and M.I. Travasso, 2014: Food security and food production systems. In: Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Field, C.B., V.R. Barros, D.J. Dokken, K.J. Mach, M.D. Mastrandrea, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L.White (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 485533.

Ross, L. G., Telfer, T. C., Falconer, L., Soto, D., & Aguilar-Majarrez, J. (2013). Site selection and carrying capacities for inland and coastal aquaculture. FAO.

Weisstein, E. W. (2002). Cellular automaton

mitigation. In K. Cochrane, C. De Young, D. Soto and T. Bahri Aquaculture Technical Paper. No. 530. Rome, FAO. pp.107-150. •

Energy and Climate Outlook 2014, Massachusetts Institute of Technology http://globalchange.mit.edu/research/ publications/other/special/2014Outlook Accessed May 25, 2015, 1:37am

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Harman, B. P., Heyenga, S., Taylor, B. M., & Fletcher, C. S. (2013). Global lessons for adapting coastal communities to protect against storm surge inundation. Journal of Coastal Research.

Hishamunda, N.; Bueno, P.B.; Ridler, N.; Yap, W.G. Analysis of aquaculture development in Southeast Asia: a policy perspective. FAO Fisheries and Aquaculture Technical Paper. No. 509. Rome, FAO. 2009. 69p.

IPCC, 2014: Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Field, C.B., V.R. Barros, D.J. Dokken, K.J. Mach, M.D. Mastrandrea, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma,

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

Coastal Biological Systems •

Barbier, E. B., Koch, E. W., Silliman, B. R., Hacker, S. D., Wolanski, E., Primavera, J., ... & Reed, D. J. (2008). Coastal ecosystembased management with nonlinear ecological functions and values. science, 319(5861), 321-323.

Broadhead, J., & Leslie, R. (2007). Coastal protection in the aftermath of the Indian Ocean tsunami: What role for forests and trees?. Rap publication, 07.

Chindapol, N., Kaandorp, J. A., Cronemberger, C., Mass, T., & Genin, A. (2013). Modelling growth and form of the scleractinian


coral Pocillopora verrucosa and the influence of hydrodynamics. PLOS Comput. Biol, 9(1), 1-15. •

Ferrario, F., Beck, M. W., Storlazzi, C. D., Micheli, F., Shepard, C. C., & Airoldi, L. (2014). The effectiveness of coral reefs for coastal hazard risk reduction and adaptation. Nature communications, 5.

Koch, E. W., Barbier, E. B., Silliman, B. R., Reed, D. J., Perillo, G. M., Hacker, S. D., & Wolanski, E. (2009). Non-linearity in ecosystem services: temporal and spatial variability in coastal protection. Frontiers in Ecology and the Environment, 7(1), 29-37.

Koehl, M. A. R. (1984). How do benthic organisms withstand moving water?. American Zoologist, 24(1), 57-70.

Latief, H. and Hadi, S. (2007). Chapter 1 – Protection from Tsunamis in Broadhead, J., & Leslie, R. (2007). Coastal protection in the aftermath of the Indian Ocean tsunami: What role for forests and trees?. Rap publication, 07.

Man-made Coastal Structures

Waterway, Port, Coastal, and Ocean Engineering, 139(1), 1-8. •

Seabrook, S. R., & Hall, K. R. (1998). Wave transmission at submerged rubblemound breakwaters. Coastal Engineering Proceedings, 1(26).

Sollitt, C. K., & Cross, R. H. (1972). Wave transmission through permeable breakwaters. Coastal Engineering Proceedings, 1(13).

WEB REFERENCES •

https://www.ipcc.ch/ [Accessed August 15, 2015]

Chapter 7 – Breakwaters http://news.mongabay.com/2014/12/ reefs-reduce-97-percent-of-wave-energy-could-be-better-

http://oceanservice.noaa.gov/[Accessed, June 2, 2015]

What is Aquaculture? (http://www.nmfs.noaa.gov/aquaculture/ what_is_aquaculture.html), [accessed August 19, 2015, 11:05am]

• structures. InPaper ofr Seminar of Teori dan Aplikasi Teknologi Kelautan IV, Surabaya. •

• environment. Issues Fact Sheets. Text by Uwe Barg. In: FAO Fisheries and Aquaculture Department [online]. Rome. Updated 27 May 2005. [Cited 25 August 2015]. © FAO 2005-2015. http://

Arnouil, D. S. (2008). Shoreline Response for a Reef Ball TM Submerged Breakwater System Offshore of Grand Cayman Island (Doctoral dissertation, Florida Institute of Technology).

• Science, 44(2), 934-941. •

Cheng, L. H., Fen, C. Y., Li, Y. H., & Jiang, W. Y. (2013). Experimental study on a new type floating breakwater.

d’Angremond, K., Van Der Meer, J. W., & De Jong, R. J. (1996). Wave transmission at low-crested structures. Coastal Engineering Proceedings,1(25).

Dong, G. H., Zheng, Y. N., Li, Y. C., Teng, B., Guan, C. T., & Lin,

www.fao.org/docrep/013/i1883e/i1883e07.pdf

www.unep.org/geo/geo4/media/GEO4-20SDM_launch.pdf [Accessed May 15, 2015, 5:25pm]

floating breakwaters. Ocean Engineering, 35(8), 931-938. •

Elchahal, G., Younes, R., & Lafon, P. (2009). Parametrical and Motion Analysis of a Moored Rectangular Floating Breakwater. Journal of Offshore Mechanics and Arctic Engineering, 131(3), 031303.

• stabilization and habitat enhancement. In Proceedings of the • coastal erosion protection with aquaculture and recreational amenities. Reef Journal,1(1), 235-246. •

Pena, E., Ferreras, J., & Sanchez-Tembleque, F. (2011). lines and module connector forces with different designs of floating breakwaters. Ocean engineering, 38(10), 1150-1160.

Ruol, P., Martinelli, L., & Pezzutto, P. (2012). Formula to predict

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APPENDIX

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APPENDIX -1 LBM METHOD FOR CFD Coding Evironment: Rhino3d -> Grashhopper -> Python Library Used: tions and simulations. Number of Lines: 127

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APPENDIX -2 WAVE CALCULATION AND REDUCTION Coding Evironment: Rhino3d -> Grashhopper -> CSharp Library Used: Number of Lines: 330 Notes: This is the second version rewrite in C# which is ten times faster than the previous version written in Python.

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APPENDIX -3 WAVE CALCULATION AND REDUCTION

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APPENDIX

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APPENDIX - 4 GENERATING NETWORK AND CALCULATION Coding Evironment: Rhino3d -> Grashhopper -> Python Library Used: NetworkX Number of Lines: 86 Notes: with graph data structure are ready to use.

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APPENDIX - 5 BINARY SEARCH FOR MAXIMUM DENSITY Coding Evironment: Rhino3d -> Grashhopper -> CSharp Library Used: NetworkX Number of Lines: 86 Notes: with graph data structure are ready to use.

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APPENDIX - 6 PLATFORM MORPHOLOGY GENERATION WITH CA (PYTHON) Plaform Mophology Generating with CA(Python) Coding Evironment: Rhino3d -> Grashhopper -> Python Library Used: tions and simulations. Notes: With the help of matrix calculation, Cellular Automata and way.

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219


APPENDIX - 7 MORPHOLOGY GENERATION G1-4 COMPARISON Ranking

1

2

3

4

G1

G1.4 Total Volume (m3) : 4104 Surface Area (m2) : 3708 Average Deformation (m) : 0.076

G1.1 Total Volume (m3) : 4644 Surface Area (m2) : 4374 Average Deformation (m) : 0.079

G1.3 Total Volume (m3) : 4806 Surface Area (m2) : 4752 Average Deformation (m) : 0.093

G1.5 Total Volume (m3) : 4131 Surface Area (m2) : 3744 Average Deformation (m) : 0.102

G2 G2.19 Total Volume (m3) : 4104 Surface Area (m2) : 3708 Average Deformation (m) : 0.076

G2.12 Total Volume (m3) : 4644 Surface Area (m2) : 4374 Average Deformation (m) : 0.079

G2.05 4914 Total Volume (m3) : 4608 Surface Area (m2) : Average Deformation (m) : 0.089

G2.22 4806 Total Volume (m3) : 4752 Surface Area (m2) : Average Deformation (m) : 0.093

G3 G3.13 Total Volume (m3) : 3618 Surface Area (m2) : 3474 Average Deformation (m) : 0.072

G3.21 Total Volume (m3) : 4644 Surface Area (m2) : 4374 Average Deformation (m) : 0.079

G3.03 4104 Total Volume (m3) : 3708 Surface Area (m2) : Average Deformation (m) : 0.076

G3.05 5697 Total Volume (m3) : 4824 Surface Area (m2) : Average Deformation (m) : 0.083

G4 G4.01 Total Volume (m3) : 3726 Surface Area (m2) : 3582 Average Deformation (m) : 0.067

220

G4.19 Total Volume (m3) : 3618 Surface Area (m2) : 3474 Average Deformation (m) : 0.072

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G4.03 3942 Total Volume (m3) : 3888 Surface Area (m2) : Average Deformation (m) : 0.077

G4.24 4644 Total Volume (m3) : 4374 Surface Area (m2) : Average Deformation (m) : 0.079


5

6

G1.6

G1.2

Total Volume (m3) : 5643 Surface Area (m2) : 4770 Average Deformation (m) : 0.095

G2.03 4131 Total Volume (m3) : 3744 Surface Area (m2) : Average Deformation (m) : 0.102

G3.16 4914 Total Volume (m3) : 4608 Surface Area (m2) : Average Deformation (m) : 0.089

G4.11 4104 Total Volume (m3) : 3708 Surface Area (m2) : Average Deformation (m) : 0.076

Total Volume (m3) : 5670 Surface Area (m2) : 4878 Average Deformation (m) : 0.101

G2.14 5643 Total Volume (m3) : 4770 Surface Area (m2) : Average Deformation (m) : 0.095

G3.25 4806 Total Volume (m3) : 4752 Surface Area (m2) : Average Deformation (m) : 0.093

G4.13 5697 Total Volume (m3) : 4824 Surface Area (m2) : Average Deformation (m) : 0.083

7

G1.11 Total Volume (m3) : 6075 Surface Area (m2) : 5400 Average Deformation (m) : 0.104

G2.11 6075 Total Volume (m3) : 5400 Surface Area (m2) : Average Deformation (m) : 0.104

G3.11 5940 Total Volume (m3) : 4896 Surface Area (m2) : Average Deformation (m) : 0.088

G4.20 4914 Total Volume (m3) : 4608 Surface Area (m2) : Average Deformation (m) : 0.089

8

G1.12 Total Volume (m3) : 5373 Surface Area (m2) : 4824 Average Deformation (m) : 0.11

G2.20 5670 Total Volume (m3) : 4878 Surface Area (m2) : Average Deformation (m) : 0.101

G3.22 5643 Total Volume (m3) : 4770 Surface Area (m2) : Average Deformation (m) : 0.095

G4.07 4806 Total Volume (m3) : 4752 Surface Area (m2) : Average Deformation (m) : 0.093

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APPENDIX -8 MORPHOLOGY GENERATION G1, G14, G20, G40 COMPARISON Ranking

1

2

3

4

G1

G1.4 Total Volume (m3) : 4104 Surface Area (m2) : 3708 Average Deformation (m) : 0.076

G1.1 Total Volume (m3) : 4644 Surface Area (m2) : 4374 Average Deformation (m) : 0.079

G1.3 Total Volume (m3) : 4806 Surface Area (m2) : 4752 Average Deformation (m) : 0.093

G1.5

Total Volume (m3) : 41 Surface Area (m2) : 37 Average Deformation (m) : 0.

G14

G14.2 Total Volume (m3) : 3483 Surface Area (m2) : 3582 Average Deformation (m) : 0.044

G14.1 Total Volume (m3) : 3888 Surface Area (m2) : 3798 Average Deformation (m) : 0.053

G14.5 Total Volume (m3) : 2997 Surface Area (m2) : 2880 Average Deformation (m) : 0.051

G14.6 Total Volume (m3) : 3834 Surface Area (m2) : 3798 Average Deformation (m) : 0.054

G20 G20.6 3483 Total Volume (m3) : 3582 Surface Area (m2) : Average Deformation (m) : 0.044

G20.1 3726 Total Volume (m3) : 3618 Surface Area (m2) : Average Deformation (m) : 0.048

G20.4 3780 Total Volume (m3) : 3744 Surface Area (m2) : Average Deformation (m) : 0.054

G20.2 3888 Total Volume (m3) : 3798 Surface Area (m2) : Average Deformation (m) : 0.053

G40 G40.3 3186 Total Volume (m3) : 3168 Surface Area (m2) : Average Deformation (m) : 0.034

222

G40.4 3348 Total Volume (m3) : 3474 Surface Area (m2) : Average Deformation (m) : 0.041

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

G40.1 3591 Total Volume (m3) : 3510 Surface Area (m2) : Average Deformation (m) : 0.044

G40.5 3861 Total Volume (m3) : 3744 Surface Area (m2) : Average Deformation (m) : 0.045


131 744 .102

5

6

G1.6

G1.2

Total Volume (m3) : 5643 Surface Area (m2) : 4770 Average Deformation (m) : 0.095

G14.4 Total Volume (m3) : 3375 Surface Area (m2) : 3384 Average Deformation (m) : 0.055

G20.5 4077 Total Volume (m3) : 3942 Surface Area (m2) : Average Deformation (m) : 0.056

G40.6 4077 Total Volume (m3) : 3798 Surface Area (m2) : Average Deformation (m) : 0.044

Total Volume (m3) : 5670 Surface Area (m2) : 4878 Average Deformation (m) : 0.101

G14.3 Total Volume (m3) : 3699 Surface Area (m2) : 3870 Average Deformation (m) : 0.057

G20.3 4185 Total Volume (m3) : 4032 Surface Area (m2) : Average Deformation (m) : 0.057

G40.6 3807 Total Volume (m3) : 4050 Surface Area (m2) : Average Deformation (m) : 0.050

7

G1.11

8

G1.12

Total Volume (m3) : 6075 Surface Area (m2) : 5400 Average Deformation (m) : 0.104

Total Volume (m3) : 5373 Surface Area (m2) : 4824 Average Deformation (m) : 0.11

G14.14

G14.32

Total Volume (m3) : 3672 Surface Area (m2) : 3906 Average Deformation (m) : 0.059

Total Volume (m3) : 4104 Surface Area (m2) : 3978 Average Deformation (m) : 0.062

G20.21

G20.11

4239 Total Volume (m3) : 4050 Surface Area (m2) : Average Deformation (m) : 0.059

4536 Total Volume (m3) : 4518 Surface Area (m2) : Average Deformation (m) : 0.063

G40.23

G40.12

4239 Total Volume (m3) : 3978 Surface Area (m2) : Average Deformation (m) : 0.046

3375 Total Volume (m3) : 3636 Surface Area (m2) : Average Deformation (m) : 0.050

APPENDIX

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APPENDIX -9 TEST SITE LAND BASED VILLAGE POPULATION 0

10

30

1

SITE

2

village 1 Qida 2 Shaâ&#x20AC;&#x2122;ao 3 Chicai 4 Fishing Rafts

3

area (km2) 0.35 0.27 0.21 3.04

population PD (per km2) 5528 15,794 2300 8,518 1500 7,142 625 1900

The diagram shows the population around the site and includes the data

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(m)


APPENDIX -10 SITE CONTEXT AQUACULTURE PRODUCTION & TYPHOON SCENARIO

Marine Products, and Marine Aquaculture and Fishing (2011)

Marine Products, and Marine Aquaculture and Fishing (2011) Aquatic products

Division Site Problems :

Output (ton)

Marine products

Marine products Output(ton)

Typhoon effects on Aquaculture floating settlement Fujian

6037800

5262035

- Lost and damage of floating houses and aquaculture.

Xiapu County

307158

306790

Aquaculture products %

Area(mu)

Fishing products

Output(ton)

%

Output(ton)

%

87.15

2134800

3161489

60.08

2100546

39.92

99.88

261720

207514

67.64

99276

32.36

General scenerio

Typhoon scenerio

120

120

120.2

120.2

27

27

Pacific surge

Site

26.3

26.3

land aquaculture farm and settlement Over-crowded port Available port Fisherman boat

APPENDIX

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APPENDIX -11 SITE CONTEXT WIND AND TIDE DATA 1 APR to 31 OCT Wind Data The wind data shows two main prevalent wind directions in different seasons.

1 NOV to 31 MAR

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Tide Data The tida data shows the tide range and the timetable in a day. The tide difference reachs 5 meters in a tidal movement.

6 5 4 3 2 1 0 -1 -2 -3

5

6

7

8

9

10

11

12

13

14

15

16

2

3

20

21

22

23

24

25 27 29 30

AM High tide AM Low tide PM Low tide

19

28

1

PM High tide

18

26

4

-4

17

Sea Level :0 Chart Datum

Highest Tide : 8.21m Tidal Range : 4.8 m Lowest Tide : 0.35m

APPENDIX

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APPENDIX -12 EXISTING AQUACULTURE FISH CAGE TYPOLOGIES

Basic Components of Floating Culture Cage

working platform buoy floating system

fish net

weight

anchor

Fish Cages Raft cage culture is the majority of traditional way in aquaculture nowadays, due to it is easy to adapt the sea condition and provide stable harvest. However, have to use tradition type of culture cage to survive, which is the cheapest culture cage and easy to repair. The material used for these cages are collected from local market, which include bamboo, wooden boards, steel pipes and polyvinyl chloride or nylon nets. In terms of storm situation defence capability, most of them are easily be destroyed. For this concern, people has created varied type of culture cages which are and wind velocity. There are mainly two type of cages, inshore culture cage and offshore culture cage. Inshore cage has three problems: First, there is not enough space for future expansion. Second, the cages cannot 228

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lives and property is threatened by this annual disaster. Third, inshore cage farming causes severe residuals, inducing outbreaks of disease and parasitic infections.


Traditional Cage

HDPE Cage

size(m): 3*3*5

Metal Frame Grvity Cage

Flating Rope Cage

Sea Station Cage

SLW Cage

size(m): 10*10*8

size(m): 6*6*6

size(m): 3*3*5

size(m): 10(Ă&#x2DC;)*20(L)

walkway(m): 0.3

walkway(m): 1

walkway(m): 2

walkway(m): 0

walkway(m): 0

walkway(m): 0

material: 1. bamboo 2. wooden boards

material: 1. HDPE pipes 2. nylon nets

material: 1. steel 2. nylon nets

material: 1. polypropylene 2. polyethylene

material: 1. steel 2. nylon nets

material: 1.steel 2. nylon nets

cost

cost

cost

cost

cost

cost

capacity against wind (km/hr)

capacity against wind (km/hr)

capacity against wind (km/hr)

capacity against wind (km/hr)

capacity against wind (km/hr)

capacity against wind (km/hr)

40 capacity against wave (m) 3

capacity of sea depth (m)

15 capacity of people

60 capacity against wave (m)

70 capacity against wave (m)

4

capacity of sea depth (m)

40 capacity of people

70 capacity against wave (m)

capacity against wave (m)

7

5

capacity of sea depth (m)

capacity of sea depth (m)

30

30

capacity of people

capacity of people

90

80 capacity against wave (m)

7

capacity of sea depth (m)

7

capacity of sea depth (m)

50 capacity of people

50 capacity of people

APPENDIX

229


APPENDIX -13 OTHER MOORING SYSTEM PRINCIPLES Anchoring Vessels and Scope Holding Power Anchor

Rode, Length (Rope or Chain)

Buoy

Floating Vessel

Water Depth

Scope = Ratio of Rode to Water Depth

Scope

2:1

3:1

5:1

7:1

10:1

Holding Power

10%

40%

70%

85%

100%

Select Parts of Mooring System

230

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015


Mooring System of a Typical Pontoon Type Breakwater

Connection

Catenary System

Anchor

Parts of An Anchor

Taut Type System Catenary Type Only subjected to horizontal forces. Restoring forces are aided by the weight of the mooring line as well.

Illustations (Left & Above) adapted from Anchor Manual 2010, available from www.vryhof.com

Taut Type System Anchor point must be able to resist vertical and horizontal forces.One advantage over catenary system is the footprint of similar application is less. Forces experienced is dependent on the elasticity of the mooring line.

APPENDIX

231


APPENDIX - 14 WAVE ANALYSIS AND FORECASTING NOMOGRAM (BRETSCHNEIDER, 1970)

kt

Wave Analysis and Forecasting Nomogram (Bretschneider, 1970)

100

6

90

70

10

10 15

12

12 20

25

14 30

16 40

18

20

50

60

24

36 48

70

100 90 80

4

60

4

Violent Storm Storm

50 45 40 Wind Speed (Knots)

Gale Near Gale

8

6

80

8

3

35

2

30 26 22 18

1

1

2

4

6

12

18

60 72

96

2

14 12 10 1

2

4

10

20

40

Fetch Length (Nautical Miles)

1 ft = 3.28 meters

232

ADAPTIVE FLOATING SETTLEMENTS - AA EMTECH DISSERTATION 2015

80

150

300

450

nmi 750 600 1000


APPENDIX

233


Adaptive Floating Settlements is a dissertation that investigates on integrating different strategies to address wave energy reduction and develop organizational logics of floating settlements centered around the aquaculture activity. This is in response to the compound effects brought about by coastal migration, rapid changes caused by climate change and increasing demand for food. The research was contextualized in Xiapu County, Fujian China, where an existing aquaculture industry with floating settlements are thriving, but face vulnerabilities due to frequent storms bringing destructive waves that damage property and the lack of a system to address thereof, as well as the consequences of an â&#x20AC;&#x2DC;informalâ&#x20AC;&#x2122; or self-organized settlement. Data on the siteâ&#x20AC;&#x2122;s existing aquaculture, and socio-economic

conditions were gathered, precedents such as existing wave attenuation system structures including coastal biological systems and man-made structures are analyzed to abstract principles and parameters to inform the development of design ambitions and strategies. Through experiments, development of analytical tools and algorithms, an integrated strategy was achieved where wave attenuation served as the major driver for pattern arrangements, followed by aquaculture and social logics to influence the development of an emergent and adaptive organizational logic for coastal floating settlements.

Keywords: floating settlements, adaptive, wave reduction system, settlement logics, pattern, aquaculture

James 1: 2 -8

This dissertation is printed on recycled paper.


[EmTech] 2015

James 1: 2 -8

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ADAPTIVE FLOATING SETTLEMENTS (AA EmTech MSc Thesis)  

An Investigation to integrate strategies of wave height reduction and aquaculture activity to develop organizational logics of floating sett...

ADAPTIVE FLOATING SETTLEMENTS (AA EmTech MSc Thesis)  

An Investigation to integrate strategies of wave height reduction and aquaculture activity to develop organizational logics of floating sett...

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