Technical Dissertation

80Hz

200Hz

30Hz

SUBMERGING SOUNDSCAPES A comparison of architecture’s sonic qualities under water versus above water.

Kiran Gosal Technical Tutor: Donald Shillingburg Tutors: Chee-Kit Lai and Doug John Miller Unit 9 at The Bartlett School of Architecture

KIRAN GOSAL

CONTENTS

01 INTRODUCTION 1. international site context 2. local site context 3. site as a test bed 4. programme 5. concept 6. initial developement 02 UNDERSTANDING FREQUENCY 7. timelines 8. frequency tracking 9. how sound travels through water and spectrograms 03 TIDAL MOVEMENT [environmental focus] 10. understanding the tide 11. the tide on-site 12. environmental section [ventillation strategy] 13. acoustic section 14. material palette and carbon neutrality

18. pachyderm sound simulations 19. comparing methods 20. pond design 05 USING FREQUENCY TO ENGINEER [structural focus] 16. densities 17. material resonant frequencies 18. material audio tests 19. wall gradient (ground boundary) 20. sonic roofing (ceiling boundary) CONCLUSION BIBLIOGRAPHY IMAGE SOURCES

04 CONTROLLING THE SONIC LANDSCAPE [technical focus] 15. frequency analysis 16. blender fluid simulations 17. blender sound simulations [sound bricks]

abstract

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KIRAN GOSAL

ABSTRACT

SUBMERGING SOUNDSCAPES

The dissertation is an investigation into underwater acoustics, and how the sonic landscape is altered once submerged. Frequency is an integral part of the study, understanding how it can be manipulated, what it’s properties are and how it can ultimately be used to promote growth, create different levels of comfort and alter environments completely.

Frequency will also be used as an engineering tool in the structural segment of the dissertation. The overarching aim is to understand how the sonic qualities of the proposal, a bioacoustics research centre, act underwater and above water. Finding a simulation that allows for accurate analysis of sound travelling through water is a critical approach taken in the dissertation. This is also later compared with physical tests using personal parameters, aiming to outline a strategy in which the building acts as an archive of frequencies which alter different user experiences in different ways.

RESEARCH QUESTIONS

How does the building’s sonic output change when submerged in the flood?

Which simulation/physical method allows for a clear understanding of sound’s propogation through water?

How is frequency used to promote biodiversity, health and alter environments?

KEY TERMS : bioacoustics: bioacoustics is the cross-disciplinary science of biology and acoustics, looking into how animals interact through sound . soundscape: what the landscape sounds like, and how this changes. acoustic gradient: when frequencies or decibel level increases or decreases on a gradient

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ROTTERDAM

On visiting Rotterdam, something that was evident was the significant amount of flood infrastructure. Due to Rotterdam being the world’s biggest port, I was particularly drawn to the aquatic environment and began investigating underwater noise pollution. Due to ship traffic, which was something that Rotterdam has been exposed to since before World War II, the underwater habitat is something that has suffered and been altered historically. Therefore, choosing a site which allowed for an investigation into mitigating sound pollution was essential to the research.

F01

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INTERNATIONAL SITE CONTEXT

Rotterdam is a city known for its flood infrastructure and shipbuilding regimes. However, this does not eradicate the fact that soon most of the area will be underwater, the cities major problems being coastal flooding, and noise pollution from port works. This also includes underwater noise pollution, which is generated due to the amount of ship traffic covering the coast. The 1:1250 map showcases the areas prone to flooding, as well as the concentration of noise polluted areas.

site photo, the tide and surrounding context

1:1250 site map, exploring flooding and noise pollution

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SITE AS A TESTBED

Stormpolder is an isolated island forty minutes from Rotterdam’s city centre, containing a working port which is based primarily around metal work and shipbuilding. The ‘flood forest’ lies on the left of the port, earning its name by hosting bidaily floods which affect the whole area of the forest.

These floods can occur within the hour, so safety and tidal movement is something the building will have to consider.

A

6

7

3

1

site sections showing the forests relationship to the water

0

25

NIEUWE MAAS

SILKSLOOT

50

100m

4

2

B STUDIO IGNOR

MUSEUM - DE ARK VAN NOACH

METAL SCRAPYARD

KRIMPEN AAN DEN IJSSEL

B

SHIP BUILDERS

EILAND DE ZAAG

5

SITE

A

daily tide fluctuations

VARIABLES 01 material waste output 02 flooding (twice a day)

03 yearly tide fluctuations 04 shore biodiversity

05 underwater sound from ship traffic 06 noise pollution from ports 07 weather conditions 08 earth boudaries

0

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25

50

100m

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PROGRAMME INTRODUCTION

TYPOLOGIES OF THE BIOACOUSTIC RESEARCH CENTRE

The chosen programme is a bioacoustics research centre, designed to help foster biodiversity in the local area. Using frequencies on-site and generated frequencies to create a sonic landscape that changes with the different eras of the building.

When beginning my research surrounding the typology, I looked into sound installations that manifested this aesthetic and conceptual goal. As well as conventional research centres that interacted with the ground in a way that could be learnt from.

entrance 2

relief from port noise pollution

ACOUSTICS AND SIGNALLING

13

utilising the flood

02

14

03

METAL

WATER

re-use of maritime materials

12

15

entrance 3

F01 WETLAND RESEARCH AND

01

entrance 1 64m

01

material flows

EDUCATION CENTRE

10

09 04

11 06

07

tidal analysis

08

scrap metal usage

05

16

40m

Scattering architecture to allow for protection of habitat.1

03

17

18

frequency analysis

02

01 communal space 02 storage 03 acoustic material test room(s) 04 scrap metal sorting bay

05 break room 06 submerged research space (1) 07 partially submerged research space 08 submerged research space (3) 09 health and safety/security check 10 changing rooms 11 accomodation 12 public toilets 13 meeting room 14 frequency research archive 15 broadcasting station 16 research vessel bay (1) 17 research vessel bay (2) 18 research vessel bay (3)

BIOACOUSTIC RESEARCH CENTRE

F02 POLYPHONY - UVA Audio-visual installation that invites visitors to contemplate the role of sound in our world - the biophony of our environment has shaped human language, songs etc.2

“Wetland Research and Education Center / Atelier Z+,” ArchDaily, December 16, 2021, https://www.archdaily.com/973638/ wetland-research-and-education-center-atelier-z-plus.

2 “Polyphony / United Visual Artists,” United Visual Artists, December 16, 2023, https://www.uva.co.uk/features/polyphony.

1

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UNDERSTANDING SOUND the fundamentals of sound propogation and frequency

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CONSTRUCTIVE AND DECONSTRUCTIVE INTERFERENCE

SOUND PROPOGATION : AIR/WATER Sound travels through water four times faster than in air due to the particle arrangement.3 (F03) Sound is a longitudinal wave, which is a vibration that occurs in the same direction that the wave is propagating.

The project touches on four types of waves: water waves, sound waves, radio waves and light waves, however the focus is on sound waves.4

Deconstructive interference is when two waves travelling in the same direction meet and the waves cancel out, whereas constructive interference is when the waves amplify the sound (the sound is doubled).

LONGITUDINAL WAVE TRANSVERSE WAVE -

OCEAN ACOUSTICS

SLOWEST

Ocean acoustics is the study of sound underwater, specifically in the sea.

When objects vibrate underwater, it creates sound-pressure waves which compress and decompress water molecules as the sound wave travels.6

AIR

Marine soundscapes are different to soundscapes above water, sound typically traves faster and with more clarity through water. The ocean’s frequencies are usually on average lower frequencies, around 30Hz, which can be harmful to some mammals, specific frequencies utilised in the dissertation and project will be illustrated in the next section.7

WATER

BEHAVIOURAL ECOLOGY

FASTEST

F03

UNDERSTANDING SOUND

STEEL

geographical distribution, mating system

how sound travels through different densities

ACOUSTIC BEHAVIOUR animal call rate, vocalization type

Radio and light are on the electromagnetic spectrum (F04), this means they can travel through a vacuum, not needing any physical mass to propagate through, they are transverse waves. Underwater noise pollution is evident on the chosen site, due to ship traffic being prominent.

This harms marine animals, as it prevents them from hearing natural ocean noises, and pushes them from their natural habitats - in extreme cases the pollution can even change their migration patterns.5

ABIOTIC FACTORS wind, ice

MARINE SOUNDSCAPE

BIOTIC FACTORS prey, predators

ANTHROPOGENIC FACTORS warmer water due to climate change, vessel noise

F06

F04

electromagnetic spectrum

Robert J Urick, Sound Propagation in the Sea, 1979.

Ibid 5 Sharon Coan, How Sound Moves (Huntington Beach, Ca: Teacher Created Materials, 2015).

3 4

diagram explaining factors that alter the marine soundscape

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6“ Understanding Ocean Acoustics,” Noaa.gov, 2015, https://oceanexplorer.noaa.gov/explorations/sound01/background/ acoustics/acoustics.html.

7 Robert J Urick, Sound Propagation in the Sea, 1979.

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FREQUENCY VALUES

ON-SITE FREQUENCIES

432Hz - plants and human health

PLANTS

VEHICLE PASSING BY AND INDUSTRIAL HUM

HUMANS LOW VEHICLE HUM & BIRD SONG

FISH AND MARINE LIFE

WATER CONTACTING SHORE & SHIP HUM

frequency [Hz] HUMAN

64 - 23,000

DOG

67 - 45,00

CAT

45 - 64,00

BIRD TYPE I

250 - 8,000

BIRD TYPE II

125 - 2,000

BIRD TYPE III

200 - 12,000

FISH I

20 - 3,000

FISH II

50 - 4,000

FISH III

50 -1,100

PLANTS

432

Fish hearing range is much lower than humans and land animals, this may be due to underwater frequencies being in the lower-range and is caused by their environment.

SHIP PASSING BY & WATER HUM

A specific range of frequencies absorbed by plants is not available through research, however the frequency 432Hz, is known to induce plant growth, but interestingly also is reported to ‘calm’ humans, and have positive effects on health.

F07

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spectogram from AudioSpectogramCreator

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SPECTROGRAM

PREDICTING ON-SITE FREQUENCIES

Understanding how to read a spectrogram is essential for the dissertation set-up. Using on-site recordings and an online spectrogram producer I will interpret the data for later usage.

This chapter introduces the ideas of soundscapes and tidalscapes.

Analysing the site context - how frequency moves around the site and the proposal, and how the tide has an effect on this.

Spectrograms are a graphical representation of sound, they include a gradient of colours which relate to Decibels (a logarithmic unit used to measure sound level).6

The figure below displays the suggested frequencies that will be both produced by the building and the frequencies on-site that the building will interact with. This adjacency assumes the low-tide state, meaning only the parts close to the tide will be affected by underwater frequencies.

High pitch sound Power Spectral Density Low pitch sound port noise pollution ship traffic road traffic

F08

radiowave frequencies [out]

spectogram from spectogramsBlog

Understanding the 3 axes allows for an understanding of the whole graph.

Overall, a spectrogram will show how much energy (PSD) there is at a particular frequency at a particular time.

on-site frequencies [in] [reflected] human frequencies [in]

pink and purple haze background noise.

Frequency - how many times per second the sound source vibrates.

Every sound can be split up into frequencies, a pure frequency is a sine wave (image below).

Time - How long the sound persists

amplitude

PSD - the colours in the spectrogram display the ‘loudness’ of a frequency at a given time. In the average spectrogram, colder colours represent the quieter sounds and warmer colours are louder.

tree frequencies [in]

black space - time before the spectogram was activated.

water frequencies [in]

yellow and orange lines - pronounced sound, for example human voice.

submerged pods semipermeable corridor

yellow and orange lines - increased gradient in pitch of the pronounced sound.

underwater frequencies [in]

time

Emilia Blåsten, “Trans Voice Visualized: How to Read Spectrograms,” Scinguistics, December 4, 2020, https://cramdvoicelessons.blog/spectrograms/.

broadcasting tower

bioacoustic frequencies [out]

bioac frequ oustic [refle encies cted]

LOW-TIDE [TIDE HEIGHT + 6.4M]

LOWEST LOW-TIDE [TIDE HEIGHT + 4M]

6

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ON-SITE dB AND FREQUENCY DATA

CONSTRUCTIVE INTERFERENCE PATTERNS

To analyse on-site sound and frequencies, I used both an online decibel simulator and also my own on-site recordings to infer a base understanding of the existing sonic atmosphere of the site. The figure below displays the results of the on-site decibel mapper, using the gradient scale to infer the ‘loudness’ site in a low-tide state.

SOUND FROM THE PORT

DECIBEL - A decibel is a logarithmic unit that is utilised to measure the level of sound [how loud or quiet something is]

BARRIER [ON-SITE FENCING]

ONLY FOUR ROOF TYPES TO CHOOSE FROM

LOW-TIDE [TIDE HEIGHT + 6.4M]

LOWEST LOW-TIDE [TIDE HEIGHT + 4M]

CAN CHANGE SOUND LEVEL AND FREQUENCY

ACOUSTIC GRADIENTS CONSTRUCTIVE INTERFERENCE

This simulation had a lot of limitations in the changeable sound variables, but mostly the modelling capabilities. It is useful when understanding a general sound map of the site, and introduces ideas of decibels and frequency.

entrance 1

bioacoustic disperser broadcasting tower

bioacoustic disperser entrance 2

LOW-TIDE [TIDE HEIGHT + 6.4M]

mound - interior radio station

LOWEST LOW-TIDE [TIDE HEIGHT + 4M]

bioacoustic receiver

accomodation + WC’s

submerged pod

METAL SCRAPYARD

SOUND FROM UNDERWATER

submerged pod

entrance 3

F09 sound map produced from Noisetools.net

LOW-TIDE [TIDE HEIGHT + 6.4M]

water corridor [ gradient of permeabiliy]

https://noisetools.net/dbmap/?MYewdgZglg5gvARgDQAYkIKxIOxoEwZZ5IAsSAzKutWrdXgGQwBOUAJnABQJo85okUASnQA6DAwBGcYpzzlRCMuRTiKCUXmIJso7MRIZRJZHgBse4uV3lK5AJziRxVfYYAHOAFpk5IyaQCURR7ah40DBQ6FABCZEjg0LxdMzMwqKRI6IYANygAUwB3OHIADlEywJTQhDMgA

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LOWEST LOW-TIDE [TIDE HEIGHT + 4M]

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CHAPTER 01 TIDAL MOVEMENT [ENVIRONMENTAL FOCUS]

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GF plan [1:200 at A1]

TIDAL ANALYSIS WITH MOST RECENT ITERATION

4.6m 1.1m

50m

1.5m 2.4m

SECTION 00

RADIO TOWER FREQUENCY RECORDING BOOTHS

ENTRANCE II

EARTH MOUND PUBLIC ARCHIVE [OUTDOORS] WC

70.4m

SOUND TEST ROOM [SOUND BOOTH]

TIDAL TRACKING ROOM

SOUND BRICK/LENS MANUFACTURING ENTRANCE I

CHANGING ROOMS

3.3m

QUIET MEETING ZONE

WC

RESEARCH PONDS

5.2 m

m

7.2

LOWEST-TIDE

LOW-TIDE

HIGH-TIDE

HIGHEST-TIDE

WATER CORRIDOR [PARTIALLY PERMEABLE]

SUBMERGED [2050]

RESEARCH PONDS

WORK SPACE

2.1m

m

1.8

TECHNICAL REPORT FOCUS

35.5m

KEY VALUES The most important tidal values are the lowest-low tide [+4m] from the sea bed level shown in section, the low tide [+6.4m], the high-tide [+7.9m] and the highest-high tide [+9m]. These values are all averages. In 2050 the site is predicted to be fully submerged due to rising sea levels.

TIDE LINE

5.3m

CANTEEN

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WORKING SECTION [ENVONMENTAL IMPLICATIONS] Ventilation strategies and the affect of flooding on the site.

AS TIDE RISES, STRUCTURE SOLIDIFIES MORE AS THE STRUCTURE OF SOIL BECOMES INCREASINGLY BETTER.

‘well-structured’ soil

large pores

shaft

air, water and nutrients stored in pores

helix plate

‘poorly-structured’ soil

water remains near surface small pores

F13 soil composition diagram

OUTSIDE ARCHIVE - IF IT FLOODS IT IS INACCESSIBLE

HEAT ESCAPES THROUGH ANGLED WINDOWS

THE EARTH MOUND HAS A HIGH THERMAL MASS, MEANING IT WARMS THE SOUND ARCHIVE SPACE.

4.6m

1.1m 1.5m SOUND LENSES AND BRICKS GENERATING HEALTHY MARINE ENVIRONMENTS FOR FISH

2.4m

THE PONDS ARE NATURALLY COOLING TO THE ADJACENT BUILDING SEGMENTS

TECHNICAL REPORT FOCUS SOIL CONDITIONS

young dune/beach sand old dune/beach sand Dunkirk Deposits Calais Deposits Holland Peat RAIN FREQUENCY

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FREQUENCY FROM FOREST

FREQUENCY FROM FOREST

RAIN FREQUENCY

F12 soil composition diagram

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WORKING SECTION [ACOUSTIC IMPLICATIONS] Based off the simulations and material tests the dissertation demonstrates, an acoustic section has been iterated. The rationale behind the section below is shown through the next chapter, controlling the sonic landscape.

It explains in detail how this section was formulated.

ACOUSTIC CURTAIN WHICH IS TUNED TO ABSORB LOW FREQUENCIES AND ONLY LET SOME HIGH FREQUENCIES THROUGH BUT THEY DO NOT TRAVEL VERY FAR, SO THE QUIET SPACE IS SLIGHTLY OFFSET.

ACOUSTIC CURTAIN WHICH IS TUNED TO ABSORB LOW FREQUENCIES AND ONLY LET SOME HIGH FREQUENCIES THROUGH BUT THEY DO NOT TRAVEL VERY FAR, SO THE QUIET SPACE IS SLIGHTLY OFFSET.

ACOUSTIC CURTAIN WHICH IS TUNED TO ABSORB LOW FREQUENCIES AND ONLY LET SOME HIGH FREQUENCIES THROUGH BUT THEY DO NOT TRAVEL VERY FAR, SO THE QUIET SPACE IS SLIGHTLY OFFSET.

RAIN FREQUENCY

FREQUENCY FROM FOREST

RAIN FREQUENCY

FREQUENCY FROM FOREST

ACOUSTIC CURTAIN WHICH IS TUNED TO ABSORB LOW FREQUENCIES AND ONLY LET SOME HIGH FREQUENCIES THROUGH BUT THEY DO NOT TRAVEL VERY FAR, SO THE QUIET SPACE IS SLIGHTLY OFFSET.

LOWEST FREQUENCY LOW FREQUENCY MIXTURE OF FREQUENCY HIGH FREQUENCY FOREST FREQUENCY 0Hz [SILENT]

HIGH FREQUENCIES DON'T TRAVEL FAR

MIXTURE OF FREQUENCIES ABOVE GROUND

FOREST FREQUENCY CONTINUES

SOUND BRICKS ABSORBING FREQUENCY FOR QUIET SPACES

UNDERWATER LOW FREQUENCY CONTINUES

HEALTHY [LOW FREQUENCY] FISH NOISE LOWER FREQUENCIES UNDERWATER

TECHNICAL REPORT FOCUS COMBINATION OF LOW AND HIGH FREQUENCY

HIGH FREQUENCIES GET THROUGH ACOUSTIC CURTAIN TIDE SPLASH

LOW FREQUENCY FROM PRECIPITATION

ACOUSTIC GRADIENT MOVING THROUGH GROUND LEVEL [01] LOW FREQUENCY

ACOUSTIC GRADIENT MOVING THROUGH BASEMENT LEVEL [00]

MIXTURE OF LOW FREQUENCY AND HIGH [MOSTLY LOW]

ACOUSTIC SIMULATIONS SHOW FORM CREATES QUIET SPACE QUIET [COVERED BY EARTH]

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MATERIAL PALETTE AND CARBON NEUTRALITY

SCRAP SHEET METAL

STEEL EXOSKELETON

RECYCLED METAL FROM METAL SCRAPYARD ON-SITE

RECYCLED ALLUMINIUM

THE FREQUENCY GARDEN

TERRACOTA sound bricks - low carbon footprint as it is sourced from the groundm it is natural sustainable and safe to use.

‘The frequency garden’ transmits the healing frequency of 432Hz to the planted trees on-site. This promotes their growth and health. This approach will grow around the forest once tested in it’s efficacy within the research centre.

SOUND LENSES THAT FOSTER MARINE BIODIVERSITY

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300Hz

30Hz

30Hz

100Hz

100Hz

100Hz

LOW-TIDE

HIGH-TIDE

RELATIONSHIP 01 BETWEEN ACOUSTIC AND TIDAL ENVIRONMENT

RELATIONSHIP 02 BETWEEN ACOUSTIC AND TIDAL ENVIRONMENT

The research ponds that are the subject of the technical investigation, will have two sonic environments - submerged and not submerged. The frequencies present therefore change when water is present. In the low-tide, the pond is empty and is subject to echoing, whilst the sonic landscape can be predicted to obtain frequencies from 100Hz-300 Hz. These include the human voice frequency, forest frequencies and bird song.

The underwater sonic environment in the research pong will differ. Lower frequencies are present, such as 30Hz (ocean frequencies), these will overpower the high frequencies produced, which is partially the reason why our voices and other sounds sound muffled underwater.

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QUESTION 01 : How can we promote biodiversity using

frequency manipulation?

In theory, the sound lenses can be tuned to reflect very specific frequencies. It is due to the refractive index of the lens, similar to a visible light lens. These lenses would be used in the proposed building to reflect frequencies [100Hz>] that attract fish and underwater animals, in turn creating a more biodiverse tidal region. It has proven difficult to test these lenses accurately without scientific equipment. However, the programme Pachyderm Acoustic allowed for a better understanding that specific sound waves are reflected whilst others are absorbed.

iteration I

iteration II

F14 Lunenburg Lens

I iterated the lens design based off research into Lunenburg Lenses and metamaterials. These metamaterials can reflect specific frequencies of sound into the environment, based of the refractive index of the pattern.

Refractive index is how much something can refract a wave by.

LENS PLACEMENT

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CHAPTER 02 CONTROLLING THE SONIC LANDSCAPE [TECHNICAL INVESTIGATION]

The main technical investigation aims to find a digital simulation with which underwater sound can be measured and analysed accurately. The building itself aims to induce acoustic gradients throughout the building, therefore polar extremes must be identified [loud vs quiet/ low frequencies vs high frequencies]. These acoustic gradients affect both humans and underwater animals.

Understanding how sound moves through massing’s of the proposed building is essential

in finding the ‘quiet’ areas, which are then made even quieter by the designed sound absorption bricks, also designed through this chapter. The simulation tests are complimented with physical tests, which help verify any findings. The overall question of how the buildings soundscape behaves underwater in comparison to above water is attempted to be answered in this section.

KIRAN GOSAL

INTRODUCTION

The part of the building explored through the main technical investigation is the research ponds. The outcome is to design two varying ponds which provide different acoustic environments to the humans researching inside the chambers. The exteriors affect the marine life, sound lenses and bricks are integrated into the facade, which promotes the healthy underwater environment desired. The material pallet of scrap metals and concrete for absorption qualities are also investigated.

RESEARCH QUESTIONS

THE LEVEL CHANGES AND ARRANGEMENT OF ROOMS IN THE RESEARCH SPACE WILL BE DECHIPHERED THROUGH THIS CHAPTER

01

is Blender an effective programme when dealing with fluid simulations?

02

is Blender an effective programme when dealing with acoustic simulations?

03

is Pachyderm an effective programme when dealing with interior acoustic simulations?

04

can we measure underwater sound?

05

do physical experiments have a similar output to the simulations?

06

how can we use the research conducted to generate two differing aquacoustic environments in the form of research ponds?

07

how do we control the buildings acoustic gradient?

THIS CURVED FORM IS FOUND THROUGH THIS CHAPTER

THE UNDERGROUND CONDITION WILL BE DISCOVERED THROUGH THIS CHAPTER

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QUESTION 01 : is Blender an effective programme when dealing with fluid simulations?

BLENDER INTRODUCTION

Blender is an open-source 3D ‘creation suite’, supporting modelling, animation, rigging, simulation, and rendering.5 The project will be making use of the Physics simulations Blender is able to perform, it’s accuracy will be tested against another simulation later in the dissertation. Using the particle’s tab [F13] to set up both acoustic and fluid simulations, will provide an understanding of the effect of the tide on the site, as well as how different frequencies move throughout the site.

HYPOTHESIS

EARTH MOUND II [ADDITIVE]

UNDERGROUND RESEARCH LABS [SUBTRACTIVE]

CENTRAL EARTH MOUND [ADDITIVE]

UNDERWATER RESEARCH SPACE [SUBTRACTIVE]

F15 Blender particle tab interface

UNDERWATER RESEARCH SPACE [SUBTRACTIVE]

NATURAL WATER DISPLACEMENT

Blender is a known software when regarding visualisation and rendering, however the accuracy of Blender’s programmed Physics may not be the most accurate, as visualisation could have been prioritised over accuracy.

Therefore, the hypothesis is that Blender will provide a below satisfactory simulation of the real life events of water movement and sound movement, but will provide some visually interesting representations of these phenomena.

CARVING THE LANDSCAPE

The first step in the building timeline (above) is creating a landscape in which densities of soils are displaced to create ‘peaks and troughs’, and earth mounds are created to produce an acoustic environment. The original landscape is carved to provide aesthetic and acoustic environments. This ‘designed’ landscape will be tested through a fluid simulation set up in Blender, which is intended to alter the landscape simulating erosion due to tidal movement. This will mean that the ‘fluid particles’ will have to be modified to have ‘digging’ properties that will affect the landscape.

5

https://www.blender.org/about/

The carved landscape, to provide ‘natural’ acoustic variation

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QUESTION 01 : is Blender an effective programme when dealing with fluid simulations?

FLUID SIMULATIONS

HIGH TIDE

Blender allows for different parameters to be tested and altered, including permeability, pressure, scale of particles and the velocity of particles.

Creating a fluid simulation to first test the ‘partially submerged research pods, and using this framework to test other submerged parts of the building, has been simplified into three ‘aquacoustic’ environments.

- low-tide - high tide - highest high tide (speculating 2050)

PLANE HEIGHT [ABOVE GROUND LEVEL]

low-tide

high-tide

+2.4

+3.8

frame 10

frame 20

frame 1

frame 10

frame 20

LOW TIDE

frame 1

Simulation set-up

plane : particle emitter

LANDSCAPE

3.8m

2.4m

F16 Blender interface

There are also a lot of molecules at the base of the hill, meaning the structures that will go there will too have to be sealed and strong. Making the simulation in Blender allows for the changing of variables within the simulation. I can change the displacement, velocity and friction of surfaces according to the site conditions and weather the tide is low or high.

[not to scale]

TESTING THE ‘CARVED’ LANDSCAPE

Utilising fluid simulations to understand how the tide will move on the ‘carved landscape’ allows the building design to become more strategic.

The majority of water particles collect in the underground spaces, however there will be strcutrure within these. This structure will have to be as strong as possible to keep the high pressure water molecules from breaking through.

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QUESTION 01 : is Blender an effective programme when dealing with fluid simulations?

HELMHOLTZ RESONATORS

HOW SOUND PARTICLES GET ABSORBED

A Helmholtz resonator is a device consisting of a cavity (typically a hollow sphere or cylinder) with an opening (the neck), through which air can enter and exit. When sound waves travel through the opening, they cause vibrations within the cavity, resulting in resonance at a specific frequency determined by the size of the cavity and the length and diameter of the neck.

Sound gets absorbed by getting caught by the molecules in the medium it is travelling through. This is due to the kinetic energy of the particle being transferred into small amounts heat energy. Every material has different absorption qualities, usually measure via an absorption coefficient.

Helmholtz resonators are used in architectural acoustics to absorb frequencies especially lower frequencies. This could include ship traffic noise, which is of a low frequency.

AIR

F17 An early Helmholtz Resonator

SOUND ABSORBING MATERIAL

SOUND WAVE

Helmholtz resonators are used in architectural acoustics to absorb frequencies especially lower frequencies. This could include ship traffic noise, which is of a low frequency. They can be roughly ‘tuned’ to the problem frequency to help combat noise pollution.

ABSORBED SOUND WAVES

STEEL reflective material

TERRACOTTA 30dB sound absorbed

CONCRETE 0.02 absorption coefficient

An example of a Helmholtz resonator providing acoustic control is in the Elizabeth Line underground station. The station itself seems very quiet, and has good acoustic absorption qualities, this is mainly due to the Helmholtz cavities in the walls.

REFLECTED SOUND WAVES ALLUMINIUM reflective material

F19 Diagram of how sound waves are absorbed TREE BARK absorbative material

F18 Helmholtz resonator’s in the Elizabeth Line

02

technical investigation

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Kiran Gosal Design Technology

KIRAN GOSAL

QUESTION 02 : is Blender an effective programme when dealing with acoustic simulations?

SOUND BRICK ITERATION I

The simulation depicts sound particles entering the cavity,and colliding with the interior walls, therefore losing kinetic energy and being absorbed, this reduces the overall sound of the space, making the environment ‘quieter.’

The transparent simulation shows an abundance of particles getting ‘trapped’ in the corners the most. Colliding with inner cavity walls and losing Kinetic Energy before eventually being absorbed.

Using the Helmholtz Resonator form to design ‘sound bricks’ which absorb frequencies will be essential in generating quiet spaces within the sonic landscape. Setting up a sound particle simulation in blender to test the form of the proposed sound brick allows for further understanding of how the particles move through the resonator and how they are ultimately absorbed.

Using the same particle simulation as the fluid section, however the particles are programmed to act as a sound particle rather than a fluid body.

corner that absorbs the most partcles

opening to the brick

Stacking the bricks allows for a scaled up effect of absorption. In the next iteration, the shape of the brick needs to be considered more, as well as the size of the opening, as a middle point must be found. The opening needs to be big enough to let in the most particles it can, however needs to be small enough so they don’t bounce back out of the opening.

The first trial simulates a terracotta material for the brick, in which you can see the particle movement on the exterior, however you can not see how the particles act on the inside of the brick. Therefore I utilised the material nodes to change the clay texture’s transparency, to allow for a more informative simulation model.

some particles will make contact with the exterior of the brick, so terraccota is a good material to use for the purpose of absorbing sound

‘trapped’ sound particles

glass texture to see internal collisions

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QUESTION 02 : is Blender an effective programme when dealing with acoustic simulations?

SOUND BRICK ITERATION II

The particle simulation shows a higher volume of sound particles being trapped in the cavities on both sides, the thinner neck on the left hand side captures the most sound particles, as the thinner shape means they collide more in a shorter amount of time.

The next iteration utilises a more irregular shape. This would in theory ‘trap’ more sound particles as there are more crevices for the collisions to take place. The design of the brick takes inspiration from the design language of the landscape carving, constructive interference patterns and the acoustic quality of absorbing the most sound particles.

the ratio of surface area of the brick to the opening width is different, the opening takes up more space on te bricks fac, meaning it is more likely that sound will enter through the opening than the previous iteration

structural gaps in the interlocking forms, so an iteration should be done to improve the structure of stacked bricks, but keep the cavities

we can see that most particles are clustered at the end in the primary and secondary cavities

collisions take place in ‘bottle neck’ form

These bricks do not interlock seamlessly, another iteration would be valuable to help these bricks, allowing for a interlocking wall structure, however these bricks can be used in the ceilings of the office areas, to relieve noise from both underwater, and working discussions, this is shown in the render on the next page.

Having a primary and secondary cavity allows for a system in which the sound particles have two chances to be absorbed. The secondary cavity absorbs the particles that didn’t get absorbed in the first cavity.

‘trapped’ sound particles

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QUESTION 02 : is Blender an effective programme when dealing with acoustic simulations?

DETAIL 01

MULTI - USE

The sound bricks are also used in ceiling pieces throughout the building, propelled from the structural beams, in order to use the bricks internally, to relieve noise from the work spaces.

the ‘bottleneck’ is both narrow and the most exposed to the exterior noise pollution, meaning collisions happen very frequently here.

high frequencies are absorbed more easily as they don’t have a lot of energy, meaning the travel for shorter times, therefore they are absorbed in the hollow space of the brick easily.

30 Hz frequencies are not solely absorbed by the cavity, a crevice which is tuned to the frequency itself is needed.

higher frequencies are produced by wildlife on-site e.g birds and human noise pollution, these do not travel very far as they have little energy.

30Hz [absorbed]

1:1 ‘sound brick’ wall at A1 sound visualisation

100Hz 100Hz [absorbed]

loudest point

0Hz 1

terracotta sound brick

ITERATING FOR STRUCTURE

2

opening to sound brick

Iteration two of the sound bricks require editing when structure of the brick laying is taken into acount. Through iterative sketching I realised that the back of the cavity needs to be much thicker, and this will have minimal acoustic affects too as it is the same form with the same cavities, as seen in the 1:1 detail.

3

mortar joint

4

steel rail

5

stainless steel rivet

6

sound brick cavity

30Hz

higher frequencies are a lot easier to be absorbed so they are absorbed within the cavity.

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a ‘quiet’ layer is created, where there is an absence of frequency due to the frequencies being absorbed, this in turn affects thr overall ‘quietness’ of the exterior space, and the interior space, as it acts as a sound barrier.

underwater frequencies = low and harmful to the underwater environment. These frequencies are only prominent when the brick is underwater.

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QUESTION 03 : is Pachyderm an effective programme when dealing with interior acoustic simulations?

BLENDER PARTICLE SIMULATION ANALYSIS

PACHYDERM ACOUSTIC INTRODUCTION

There are positives and negatives to Blender’s physics system - it claims to allow simulations which ‘mimic’ many physical phenomena, however the accuracy within these must be scrutinized. The primary purpose of Blender is for it to be used in computer graphics, therefore there are some shortcuts made in the physics due to the ability to decrease processing time for users.

Pachyderm acoustic is a plugin for Grasshopper, which is popular amongst designers and scientists when simulating acoustics in buildings, rooms and on a larger scale. It is a collection of acoustics simulation algorithms that are used to predict how sound will travel through a space, whilst also providing a visual representation. Despite the popularity of the software, there are limited resources to understand how to use the software, so a trial and error approach is taken in the dissertation, to come to a conclusion about whether an accurate underwater sound simulation can be programmed.

HYPOTHESIS

Pachyderm acoustic will provide an accurate representation of sound travelling within interior spaces, however with my previous knowledge of Rhino and Grasshopper, I predict that simulating external sound will be harder to do accurately. This is due to the neccesity of running simulations within a closed polysurface (two or more surfaces joined at the edges), and modelling a large body of water as a closed polysurface is problematic due to a limit in the sizing, which is unrealistic.

Point - In this script, the point represents the point source where the sound is generated.

Dampening allows you to make estimates on how much each material would dampen sound, however because there are no units, an accurate number cannot be supplied

Boundary representation - a method of represenation of a 3D shape in modelling softwares, done by defining the volume limits of the closed polysurface in this case.

The rigid body is the solid that is being tested for it’s absorbtion qualities, in these cases they were the sound bricks and the landscape for the fluid simulation.

SETTING UP THE SIMULATION FOR INTERIOR SPACES

However, Blender gives the opportunity to change a vast number of variables which allow the user to have almost full control over how a particle or particle system acts. Or this is what the interface seems like, however the ability to accurately change variables is limited.

In order to initially understand how the simulation works, testing interior spaces is easier to begin with. The inputs are the point source where the sound originates from, and the closed polysurface of the form being tested.

(F0X)

Geodesic Source - This tells the simulation that the sound source radially disperses in all directions, which is accurate to how soundwaves move from a point.

Vector Star - This component is from the Pufferfish add-on. It simulates the particles moving in all directions, and is for visual clarity.

https://www.grasshopper3d.com/group/pachyderm#:~:text=185%20members,%2C%20cities%2C%20and%20other%20settings.

x

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QUESTION 03 : is Pachyderm an effective programme when dealing with interior acoustic simulations?

TESTING THE SIMULATIOIN

PACHYDERM TO VISUALISE SOUND WAVES

The simulation output shows the particles changing colour as the energy is lost from them, which is accurate to real physics. The sound is mostly absorbed where there is a harsher more defined curve, which is something to explore further. You can use pachyderm in multiple views, which is useful to see the different ways in which sound travels.

point source

when sound moves through the opening, some sound particles are dispersed in various directions.

the size of particles in the simulation [aesthetic decision] amount of frames the annimation will go on for

PLAN VIEW

how many bounces before the particles are absorbed [correlates to the strength of sound]

less particles make it through to the next room due to particles being absorbed

1st wave breaks into two waves

gradient of colour, to show energy leaving the particles

some particles get absorbed in the third rooms [third rooms away from the point source]

very few particles reach the third rooms in the plan; they have very little energy left.

clusters of particles in the wave which get ‘stuck’ - gather by the curve in the building, where they are absorbed.

AXONOMETRIC VIEW

After setting the simulation up, a base understanding of how the simulation works and the outputs it provides was essential to the work flow. I modelled an extrusion of the plan to set the test up, with a point source of sound coming from the room which is adjacent to the ponds that the chapter goes into more detail in later.

a gap of sound waves is prominent in the plan, almost a strip of silence..

After gaining a basic understanding of how the simulation works, I was able to move onto using it in the massing forms of the research spaces, and develop forms which follow specific patterns [PTO].

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QUESTION 03 : is Pachyderm an effective programme when dealing with interior acoustic simulations?

IDENTIFYING PATTERNS IN THE SIMULATION

concerntrated point

less intense sound

PERSPECTIVE VIEW

first interference pattern

sound particle wave form

do flat walls ‘squash’ sound?

acoustic gaps with regular form

ORIGINAL MASSING FORM

FRONT VIEW

APPLYING THE ‘PINCHED’ FORM

Most of the pinched forms will be by the water, enabling larger gradients to form within the building. Meaning the ‘loudest’ parts - the spaces affected by external low frequencies [underwater frequencies - 30Hz], will be adjacent to the quiet spaces which are affected by the pinched form of the building.

MODELS TESTED IN SIMULATION

EXPLANATORY DIAGRAM

acoustic gaps after several collisions PINCHED FORM

Noticing this pinched pattern in the acoustic simulation was essential in further developing the interior spaces within the building. Utilising previous research knowledge on constructive and deconstructive interference, I hypothesised that with this waveform being naturally formed, making the building a similar form could emulate deconstructive interference.

two point underwater sound source

inside crevice = exterior sound absorbing brick

pinched massing form provides spaces of acoustic isolation

sound travels more easily through this form(?)

evenly spread after several collisions

COLLISIONS TAKE PLACE BETWEEN WALLS

ACOUSTIC ISOLATION

DEVELOPED MASSING FORM

PERSPECTIVE VIEW

KEY FRAME : ‘pinched’ pattern

FURTHER DISTANCE TO TRAVEL FROM GIVEN POINT SOURCE

After experiments with pachyderm the form which provides some acoustic isolation, is the ‘pinched’ form on the left. This form is the starting point of the acoustic gradient affect desired throughout the building. It provides a space where sound is already limited, this could be due to the length it has to travel before entering the building, although this is just a speculation.

KEY FRAME : the ‘pinched’ form

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QUESTION 03 : is Pachyderm an effective programme when dealing with interior acoustic simulations?

CORRIDOR SIMULATION

INCREASING CEILING

From this simulation we can observe where the sound is more prevalant, therefore adding material/wall build up to these sections if the goal is to limit sound within these sections, creating an even more controlled acoustic environment.

The most important acoustic environment needed to be tested is the underwater pond which allows water to gather and changes the acoustic environment of the ‘corridor’, to test this affect accurately the simulation needs to be developed, due to both simulations at this stage not being able to accurately show how sound moves through water.

The corridor decreases in width and in height as the user is travelling through, creating spaces of constructive and deconstructive interference (loud and quiet spaces). These will then be added upon by wall thicknesses and textures to increase the extremes of the acoustic gradient.

EXPLANATORY DIAGRAM

MODELS TESTED IN SIMULATION

CONSTRUCTIVE INTERFERENCE CONSTRUCTIVE INTERFERENCE

DECONSTRUCTIVE INTERFERENCE

DECONSTRUCTIVE INTERFERENCE constructive interference curve

constructive interference curve

constructive interference curves (level of most sound)

horizontal interference (louder) point at which sound comes from is most consentrated vertical interference (louder)

particles with the least energy are left at the sides caught in the irregular wall shape

don’t make it to the end of the tunnel

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QUESTION 04 : how can we simulate and measure UNDERWATER sound?

NODES AND ANTINODES

LEARNING FROM THE SIMULATION

The simulation clearly shows characteristics of sound waves, revealing accuracy in the physics behind Pachyderm. One characteristic that I observed through a side view of the building model, is the formation of nodes and anti-nodes.

Re-analysing the ‘pinched’ form on the exterior of the building allows for a base understanding of how sound moves through air on the outside of the building when the tide is low. However this does not show the comparison in how sound moves through water, only air. With the aim of comparing the two mediums accurately, pachyderm this far does not provide the variables needed to analyse underwater sound propagation and how it will affect the forms.

loud point

quiet point

dispersion in more varying directions due to difference in line

area of deconstructive

gradient of sound

Adjusting the simulation to allow for a radial dispersion method allows the sound simulation to be more accurate, however in reality, there would be multiple point sources on the exterior of the building, not just two (the amount of points the processing power can handle).

Overall, when there is an irregular edge there are points in the sound simulation which show sound being absorbed at varying rates, however this kind of boundary verses a straight one allows for sound to be dispersed more affectively.

Nodes and antinodes form when resonance occurs between two parallel surfaces when spacing is equal and there are an odd number of half wavelengths which is what is observed through the section. these conditions provide a pressure (antinode) at the surface with a varying number of nodes in between. The frequency can be calculated from these waves using the formula f=nc/2l (f = frequency, n = number of nodes, c = velocity, l = length)1 1 https://www.sciencedirect.com/topics/engineering/antinode

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QUESTION 04 : how can we simulate and measure UNDERWATER sound?

Hypothesis : Using Pachyderm’s variables, the simulation can be edited through the material tab to simulate a water density, therefore allowing the sound to travel through simulated water. If this is unsuccessful, physical tests may be conducted. Comparing water and air, sound will travel faster through air.

Material properties on Pachyderm are critical to understand when aiming to simulate sound propogation through water. (Figure X) The material library in Pachyderm has set materials where you can choose from Plate glass, Plaster, Plywood, Diffuser’s and Unoccupied/Occupied.

However to further build on this collection absorption coefficients can be used.

Absorption coefficients are measurements used to determine a materials ability to absorb sound waves.

These values vary depending on the material and frequency being absorbed, a table showcasing the values for water are shown on the left these are then inputted into the simulation. This changes the visual outputs, as shown in the figure below.

The old simulation where absorption coefficients were not inputted produced more linear scattering, which is inacurate to how sound waves propagate through water, whereas the newest simulation visualises wave forms and more random particle movement.

Visual results

The first alteration to the script needs to be the point source; in this script, the source only emits ‘sound particles’ from one side. However, this is not accurate to the research done about how sound particles and emissions behave in the previous chapter ‘Understanding Frequency’. Adjusting the simulation node GeoSrc and Cull allows for the simulation to have radial distribution from the point source.

frequency absorbed

125 Hz

250 Hz

500 Hz

1 kHz

2 kHz

4 kHz

absorption coefficients

0.008

0.008

0.013

0.015

0.02

0.025

simulation 2

simulation 1

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‘sound transmitter’

‘sound receiver’

through air

through water

0.077422

lowest frequencies

0.354019 0.858273

‘sound transmitter’

0.834335 ‘sound receiver’

0.913327 0.908264 highest frequencies

0.939917

clarity

In order to set up the simulation to provide outputs which inform the research question, how can we measure underwater sound? two points need to be set. The first point is a sound transmitter, or the point source, the second point receives the waves, after they have travelled through the mediums. This simulation is affective as we can both view visual patterns and interpret results, whilst also analysing numerical results, providing a quantitative and qualitative data set.

The numerical data is formed from raytracing each particle in the simulation, traveling from the transmitter to the receiver. We can draw conclusions from this data such as the lowest frequencies are more clear travelling through water than through air, and the highest frequencies are much faster through water than through air.

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RESEARCH POND DETAIL 01

+8.00m

CONSTRUCTIVE INTERFERENCE [LOUD] [CLEARER FREQUENCIES] DECONSTRUCTIVE INTERFERENCE [QUIET] [LESS CLEAR FREQUENCIES]

+7.00m

+6.00m

01

+5.00m

02 +4.00m

03

04 +3.00m

+2.00m

05 +1.00m

6 +0.00m

06 5

-1.00m

4

07

-2.00m

7 -3.00m

POND ONE [SUBMERGED] -4.00m

01 First wave scatter, waves are already broken up due to some particles being absorbed by the concrete basin straight away.

02 The bottom of the pond seemingly

doesn’t absorb as well as the sides of the pond, this could be due to the curve profile of the basin.

03 The large gaps can be identified as

deconstructive interference (antinode’s) meaning these spaces are silent.

04 On the other side of the basin (RHS),

-5.00m

3

-7.00m

the wave is more continuous (less interference), this again is due to the curve profile being less defined on the RHS.

-8.00m

05 Constructive interference can be seen

-9.00m

where the waves cross over, these spaces will be especially loud, something to consier whilst constructing the tanks.

06 A hole shape is left over when the particles are beginning to all be absorbed

2

-6.00m

1

-10.00m

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1

screw pile

2

concrete pond

3

rising tide

4

steel bridge framing

5

insulation

6

sound brick

7

concrete foundation

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RESEARCH POND DETAIL 02

+8.00m

CONSTRUCTIVE INTERFERENCE [LOUD] [CLEARER FREQUENCIES] DECONSTRUCTIVE INTERFERENCE [QUIET] [LESS CLEAR FREQUENCIES]

+7.00m

01

+6.00m

02 +5.00m

03 05

04

+4.00m

+3.00m

+2.00m

06

+1.00m

6 +0.00m

5

-1.00m

4

07

-2.00m

7 -3.00m

POND TWO [SUBMERGED] -4.00m

01 First wave scatter, wave has comparatively more deconstructive interference, meaning more ‘quiet spaces.’

-5.00m

3

02 The bottom of the pond has many

clusters of sound particles, as the two dips below have reflected sound into the centre, this shows this space being the loudest at the beginning of the simulation.

03 The bottom remains the loudest point,

2

-6.00m

-7.00m

04 On the other side of the basin (RHS),

the wave is more continuous (less interference), this again is due to the curve profile being less defined on the RHS.

-8.00m

1

05 Constructive interference can be seen

where the waves cross over, these spaces will be especially loud, something to consier whilst constructing the tanks.

06 Silent space 07 Scattered wave forms are left over

-9.00m

-10.00m

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1

screw pile

2

concrete pond

3

rising tide

4

steel bridge framing

5

insulation

6

sound brick

7

concrete foundation

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CONCLUSION [1] : THE SONIC RESEARCH PONDS

CONCLUSION [2] : PACHYDERM ANALYSIS

The buildings over and submerged in the pond were decided due to the mapping of the constructive and deconstructive interference patterns from the simulation and drawings. The level changes and shapes enable the users to experience spaces of extremely quiet atmoshperes and extremely loud where constructive interference takes place.

The ability for flexibility in the different views, allows for an analysis from all key angles. Being able to view from the left, allows for clear analysis of the nodes and antinodes in the simulation. This makes it easier when identifying the louder points and the quieter points, essential for finding the extremes in the acoustic gradient of the building.

Pachyderm allows for accurate analysis of sound movement through different mediums, including water, allowing for numerical results as the outcome, which is essential to the project.

The visual output is comprehensive and can easily be explained for the purpose of this dissertation.

Inaccuracy still remains in the parts where the colour gradient is added, as the gradient is changeable, it doesn’t accurately tell the user about the loss of energy in the particle.

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CHAPTER 03 USING FREQUENCY TO ENGINEER [STRUCTURAL STRATEGY] 432Hz

432Hz

Frequency is a powerful when understanding the universe – ‘If you want to find the secrets of the universe, think in terms of energy, frequency and vibration’, the structural strategy of the research centre and archive utilises the background research on how frequency is absorbed and transmitted in the earlier chapter (Understanding sound), and applies it to the design development of the roof and the walls, with the aim of using structural strategies to create and induce an

acoustic gradient through the building. The strategy to do this is by identifying ‘extremes’, where the structure can be manipulated to provide an extremely quiet point to an extremely acoustically uncontrolled point, by changing forms and materials. The overall construction sequence is also outlined.

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QUESTION 01 : how can wall build ups create a gradient of sonic atmospheres?

IDENTIFYING THE GRADIENT

To apply the structural strategy inducing an acoustic gradient, the varying desired acoustic qualities must be identified throughout the building. The most prominent and repeated acoustic gradient is as you enter the building.

Using frequency to highlight the change in boundary as you enter the building can be achieved in various means, however tackling this through the walls in the entrance is the design direction chosen.

432Hz

43

2H

z

Acoustically uncontrolled spaces will physically invite the environment into the space, so in the building’s case, the tide will be welcomed into the walkway. This can be seen in Junya Ishigami’s one-kilometre-long museum, it features openings that let water flow over the museum’s floor.

1:200 @ A1

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QUESTION 01 : how can wall build ups create a gradient of sonic atmospheres?

ABSORPTION AND THICKNESS

CASE STUDY : STUDIO ANNE HOLTROP

I began testing materials typically found on-site, and experimenting with compositions in which variables including roughness would be tested for their acoustic qualities. The investigations proved that rough concrete absorbed lower frequencies.

These experiments prompted me to research Studio Anne Holltrop, and analyse the methods used for the walls in this building, as I could draw similarities from the rough and irregular texture but put it to use acoustically. The panels shown in figure X, are sandcast concrete panels, which were casted on-stie. The project only uses three materials: concrete, sand, and aluminium (for detailing). The reasoning for these panels was aesthetic and to deliver a building that is site specific, literally – as the panels were casted on the sites landscape, capturing the topography and ground textures.

METHOD 01

F19

METHOD 01 IMPROVEMENTS

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1:50 ENTRANCE DETAIL 1, 2 AND 3

ABSORBTION AND ROUGHNESS

concrete and gravel mixture

concrete and plaster mixture

black space - frequencies are absent.

+3.0m

100Hz

+2.5m

pink and purple haze background noise.

+2.0m

100Hz

yellow and orange lines pronounced sound, for example human voice.

concrete and plaster

+1.5m

30Hz

100Hz

+1.0m

yellow and orange lines increased gradient in pitch of the pronounced sound.

30Hz 30Hz steel bolted connector

+0.5m

insulation

The tests show that the rougher material absorbs the background noise, which is typically lower frequencies. These low frequencies are prominent on the site as the site submerges - water frequencies average at around 30Hz.

GRADIENT 01

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1:50 ENTRANCE DETAIL 1, 2 AND 3

+3.0m

100Hz

+2.5m

100Hz

30Hz [partially absorbed]

+2.0m

+1.5m

+1.0m

30Hz

30Hz

+0.5m

underwater frequencies coming from below the wall to create a gradient of sound for human.

GRADIENT 02

+3.0m

+2.5m

100Hz +2.0m

30Hz [absorbed]

100Hz

+1.5m

+1.0m

30Hz

30Hz

+0.5m

GRADIENT 03

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QUESTION 02 : can roofscapes further increase the acoustic gradient in the building?

CASE STUDY : OLYMPIC ARCHERY RANGE, ENRIC MIRALLES AND CARME PINOS

HYPOTHESIS

Utilising the pinched roof that was in the lateral forms, with the aim to create an even stronger gradient. The form is slowly ‘flattened’ out, and the hypothesis based on the other simulations is that the deeper the roof, the quicker the internal sound will be absorbed because more frequent collisions will take place. However, in this simulation, the external soundscape will be tested, due to aiming to understand rain frequencies on the roofscape.

This classic piece of architecture is designed to ‘choreograph’ the lighting on-site. This will create varying lighting conditions inside. the concrete slabs are tiled and prefabricated, slotting together carefully to take the irregular shapes required for the archery range. A similar process will be carried out in the building proposal.

pinched massing form provides spaces of acoustic isolation

F20

air

water

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RESULTS

Doing a physical test to begin the investigation allowed for a basic understanding of what the simulation results would be, even from hearing the sounds made from a shower source to the 3D printed roofing parts, I could speculate that the interior acoustic environment would be of a lower pitch when using the most indented roof.

Spectogram output

GRADIENT 04

high frequencies come through to the internal spaces [not desireable for human comfort]

GRADIENT 01

low frequencies [40Hz<] = dark grey

a mix of frequencies come through to internal spaces [more desireable for human comfort]

QUIETER

GRADIENT 01

LOUDER

SIMULATING RAINFALL

WATER SOURCE (SIMULATING RAIN)

ROOFING STRUCTURE

GRADIENT 04

CONTACT MICROPHONE

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SIMULATION VERIFICATION

some particles get stuck in small crevice

two waves formed

point source

random dispersion

waves overlap unlike in air

SIMULATING RAIN FREQUENCIES THROUGH AIR

more sound reflection with this gradient

waves are absorbed quicker in warter than in air

SIMULATING RAIN FREQUENCIES THROUGH SUBMERGED LANDSCAPE

The simulation overall shows that sound is moving faster in water than it is through the air. The sound in this instance represents the rain, and simulates where rain would be falling onto the roof through air, or through water.

a line of reflected sound particles

sound particles are more concerntrated in the middle of roof

The pinched space shows the sound reflecting more clearly through water, which is more helpful in understanding why there is a ‘quiet’ strip where the pinched form is. Earlier in the report i speculated that most of the waveforms had been absorbed, but actually a lot of them are reflected by the curved shape.

‘loud’ strip left over where the quiet strip would be inside (opposite)

SIMULATING RAIN FREQUENCIES THROUGH AIR

reflections make a circular shape which is constructive interference

reflections make a a ‘teardrop’ shape around box

SIMULATING RAIN FREQUENCIES THROUGH SUBMERGED LANDSCAPE

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APPLYING THE GRADIENT ROOF DETAIL 1:50

ROOF GRADIENT PROFILE 01

ALLUMINIUM ROOF

ROOF GRADIENT PROFILE 04

TIMBER SUPPORTS

WHERE THE ROOF GRADIENTS COME INTO THE DESIGN

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CONCLUSION SUBMERGING SOUNDSCAPES

The dissertation sought to understand and alter the polluted soundscapes of the ports of Rotterdam, both underwater and above water, using the Stormpolder flood forest as a pioneering test-site for other ports to learn from. The research conducted concludes that the frequency 432Hz is the optimal frequency for underwater animals to live and breed in, generating healthy underwater atmoshpheres, and frequencies from 110Hz to 315Hz have healing properties in humans. These frequencies are both made through speakers, and through form and material manipulation in the project.

The simulation that provided the most accurate results for sound’s propogation through water was the Pachyderm-Acoustic plug-in for Rhino. Both numerically and visually, it matched previous research done on underwater acoustics, and therefore provided a platform to carry out site-specific tests in the dissertation.

As visualised through these simulations, once the building is fully submerged in 2050, the frequencies produced by the building will travel further as the visuals portrayed more places of interference and a longer propogation time per frame of the simulation and the numerical values which represented clarity of frequency allowed for an understanding that all frequencies travel through water more clearly than air.

This gives the impression to both the human and underwater mammal’s ear that the proposed building is ‘louder’ underwater. Meaning it’s healing and generative properties will be more affective underwater.

KIRAN GOSAL

BIBLIOGRAPY

Fahy, F. and P. Gardonio (). Sound and Structural Vibration.

How Well Does Sound Travel Through Different Mediums? (n.d.). Available at: https://www. uspto.gov/kids/MiddleSchool-HowWellSoundTravels.pdf.

United Visual Artists. (n.d.). United Visual Artists. [online] Available at: https://www.uva.co.uk. www.youtube.com. (n.d.).

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KIRAN GOSAL

IMAGE CITATIONS F01

Wetland Research and Education Centre https://www.archdaily.com/973638/wetland-re search-and-education-center-atelier-z-plus

F12

Soil composition diagram https://edepot.wur.nl/466708

F02

Polyphony - UVA https://www.uva.co.uk/features/polyphony

F13

Soil composition diagram [02] https://edepot.wur.nl/466708

F03

Sound propogation diagram https://pressbooks.pub/sound/chapter/how-sound- moves/

F14

Lunenburg Lens diagram https://www.nature.com/articles/s41598-018-34581-7

F15

Author’s Blender interface screenshot

F16

Author’s Blender interface screenshot

F17

Helmholtz Resonator example https://www.britannica.com/science/Helmholtz-res s%20an,the%20geometry%20of%20its%20opening.

F18

Helmholtz Resonator example https://www.britannica.com/science/Helmholtz-res s%20an,the%20geometry%20of%20its%20opening.

F19

Absorption Diagram

F20

Anne Holltrop

F21

“Wetland Research and Education Center / Atelier Z+,” December 16, 2021. https://www.archdaily. com/973638/wetland-research-and-educa tion-center-atelier-z-plus.Blåsten, Emilia.

Enric Moralles

F04

Electromagnetic spectrum diagram https://hubblesite.org/contents/articles/the-electromag netic-spectrum Author’s own diagram

F06

Marine soundscape diagram re-drawn from R-Packages. “Conclusions.” Accessed April 29, 2024. https://cran.r-project.org/web/packages/PAM scapes/readme/README.html.

F07

F08

Spectogram from AudioSpectogramCreator https://convert.ing-now.com/audio-spectro gram-creator/ Spectogram for analysis https://cramdvoicelessons.blog/spectrograms/

F09

Online Decibel mapping software https://noisetools.net/dbmap/

F10

Diagram showing the moon and suns affect on the tide https://www.timeanddate.com/astronomy/ moon/tides.html

F11

Sun and moon paths on-site https://www.suncalc.org/#/51.9049,4.5831,17/2024.04 .29/22:00/1/3

IMAGE CITATIONS

F05

https://www.nature.com/articles/s41598-018-34581-7