Centre of Excellence in Smart and Sustainable Construction Research Bulletin September 2023

Research Bulletin No.8 September 5 2023 HEC Rating 2022

Digital Transformation

Research Bulletin

No.8-September 2023

EDINBURGH DUBAI MALAYSIA

Net Zero Community Development

SHAPING TOMORROW TOGETHER

Research Bulletin No.8 September 2023

Table of contents

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About us

Editorial

3 Topic of Focus: Positioning Sustainability Prof. Lynne Jack

Dr Mustafa Batikha

5 Bio-cementation: pathway towards bringing earthworks a step closer to Net Zero Dr Dimitrios Terzis and Prof. Lyesse Laloui

7 Construction and Demolition Waste Recycling at BEEAH Mohammed Sammour

11 The State of Circularity in Dubai Faisal Ali Al Rashid, Majd Fayyad and Yitong Lin

13 Ways to Incorporate Sustainable Development in the Construction Practice Dr Cheng Siew Goh

17 Hot Weather Concreting: Challenges and Current Practices Dr Samer Al Martini and Dr Reem Sabouni

20 3D Concrete Printing: A Prospect to Reform Construction?

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Haidar Alhaidary

The Role of Digital Twin Technology in Optimising HVAC Systems in the Middle East

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Omar Al Khairat, Prof. Hind Zantout and Dr Hassam Chaudhry

Adaptive Facades with ZeroEnergy Motion Mechanism Using Hygromorphic Thermo-Bimetals Programmable Material

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Dr. Rana El-Dabaa and Prof. Sherif Abdelmohsen

Lean Leadership for Delivery Excellence

36 The Role of Advanced Machine Learning in Construction Site Safety Fatemeh Mostofi, Prof. Vedat Togan and Dr Onur Behzat Tokdemir

Dr Ramez Alchamaa and Zied Dahmani

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News & Events, Partner News

Research Bulletin No.8 September 2023

About Us Centre of Excellence in Smart and Sustainable Construction (CES²C) Heriot-Watt University’s Centre of Excellence in Smart Construction (CES²C) is committed to advancing industry-led innovations in construction that will revolutionise the way we develop, manage and operate smarter cities. CES²C partners with like-minded organisations and government entities to lead the transformation of the Built Environment and development of next generation professionals for the benefit of the economy. CES²C is a global hub for disruptive thinking, a platform for collaborative research and a model for solutions development and stakeholder engagement. More details about CES²C can be found in the following link: https://www.hw.ac.uk/dubai/research/centre-excellence-smart-construction.htm

CES²C non-executive board

CES²C industy partners

CES²C’s non-executive board, chaired by His Excellency Dr Abdullah Belhaif Al Nuaimi, Former UAE Minister of Climate Change & Environment, brings together a group of expert opinions and leading voices across academia, industry and government.

Profiles of each CES²C board member can be found using the following link: https://www.hw.ac.uk/dubai/research/CES²C/non-executive-board.htm

CES²C core team Prof. Lynne Jack, Director Dr Olisanwendu Ogwuda, Manager Charlotte Turner, Strategic Marketing Manager Annette Leamy, Executive Assistant

CES²C committee (Heriot-Watt) Matthew Smith, Head of School EGIS Dr. Karima Hamani, Academic Lead for EDI Dr. Hassam Chaudhry, Academic Lead for Building Performance Dr. Yasemin Nielsen, EngD Programme Director Shameel Mohamed, Academic Lead for Architecture

How to become a CES²C partner Would your organisation like to become an esteemed industry partner of CES²C? We work with our partners with the shared goal of transforming the future of construction by driving research and innovation in the sector.

Sharing information, skills and knowledge is key to advancing industry adoption of innovative solutions. Collaboration between industry and academia offer the opportunity to shape the challenges facing the Built Environment and preparing the next generation of construction professionals with the skills and knowledge to make a step change.

For more information about partnership benefits and working collaboratively with The Centre of Excellence in Smart and Sustainable Construction please contact cescdubai@hw.ac.uk

Contact Us E-mail: cescdubai@hw.ac.uk Social Media:

Bulletin Editor & Contact Dr Mustafa Batikha E-mail: m.batikha@hw.ac.uk

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About Us

Research Bulletin No.8 September 2023

Editorial Dr Mustafa Batikha Associate Director of Research School of Energy, Geoscience, Infrastructure and Society Heriot-Watt University, Dubai, UAE m.batikha@hw.ac.uk

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n the eighth issue of the CES²C Research Bulletin “Topic of Focus” article, Professor Lynne Jack, Associate Principal (International Research), Director of the Institute of Sustainable Built Environment and Director of CES²C, takes the approaching date of COP28 to communicate a message to the leaders for new policies and researchers for providing pathways to accelerate the change toward sustainability solutions. Prof. Jack demonstrates that CES²C took the initiative by inserting the sustainability term in its new title to be CES²C (The Centre of Excellence in Smart and Sustainable Construction). Moreover, she goes through the new agenda of the CES²C to support the Net Zero, Digital Transformation and Community Development and highlights how the recent change in CES²C will benefit the UAE. This eighth issue also presents the worthy experience of well-practised authors toward the CES²C core themes: Net Zero, Digital Transformation and Community Development.

The editorial highlights in brief ten new topics as follows:

Net Zero Dimitrios Terzis and Lyesse Laloui start this theme by highlighting the benefits of using Bio-cementation in strengthening the soil, making it denser, and increasing its stability. It is good to see that the new technique enhances the bearing capacity of the soil, cohesion and friction angle.

Moreover, the Bio-cementation of the clay makes it act effectively against cracking and swelling by heavy rain. The authors propose shallow-depth bio-cementation, which is much cheaper than the deep geological storage of carbon and easier for monitoring and control. They see that it is the long-term solution for carbon storage to support sustainability and enhance the soil’s properties.

In the second article, Mohammed Sammour explores the history of BEEAH, the waste treatment company in Sharjah and the partner of Sharjah Municipality, to achieve zero waste to landfill. In BEEAH, the CDW facility can take an annual 650,000 tons to produce and sort Recycled Concrete Aggregate of size below 50mm for mainly backfilling purposes. However, the finer aggregate was successfully tested for producing interlocks, curbstones, hollow blocks, and solid blocks. The article highlights the challenges faced by BEEAH in the market and the strategy followed to address them. Today, BEEAH is delivering about 30% of the road base in partnership with the UAE Ministry of Energy and Infrastructure. However, BEEAH has started an initiative plan to produce Solid Recovered Fuel (SRF)in its facility.

In the third article, Faisal Ali Al Rashid, Majd Fayyad and Yitong Lin explore the circular economy principles that fast-growing cities such as Dubai need. It is about eliminating waste and pollution, circulating products and materials and regenerating Nature. As applications, the article brings the circular economy policies of China and Europe for further study to develop an approach for Dubai. To support this, a Dubai circular economy committee was established in 2021 by many stakeholders to support building a policy framework. The committee’s strategy is highlighted in the article, together with the achievements to date.

The fourth article under this theme is by Cheng Siew Goh, who discusses her two recent publications on how innovative project management approaches will develop sustainable construction projects. The author points out that the linear process in conventional management doesn’t allow close effective coordination among project stakeholders. The article proposes the Integrated Project Delivery (IPD) approach, where all stakeholders collaborate together at an early stage of the project to meet the sustainable goals set by the owner. This needs to be accompanied by a sustainable procurement which achieves value for money on a whole life cycle and reduces the negative impacts on the environment.

Finally, Samer Al Martini and Reem Sabouni offer their research experience with concreting work in hot weather, which exceeds the recommended temperature by standards. The article presents challenges facing fresh concreting at high temperatures, such as the reduction of compressive strength, workability and setting times. However, the paper doesn’t leave the reader without solutions like using cool water in the mix, reducing the cement volume using GGBS and Fly Ash, keeping the aggregate as cool as possible, and using chemical admixtures. The authors ask for balancing the admixture when used in hot-weather countries because it was primarily produced in moderate-temperature countries.

Digital Transformation Haidar Alhaidary, in the first paper, presents his experience with 3D Concrete Printing technology through his work in Middle East Engineering Technologies (MEET) villa based in Sharjah, one of the first printed houses in the region. The author details the printing process and the structural systems used in the printed villa, besides the insulation benefits, which reach 16 degrees Celsius indoor temperature from 60 degrees Celsius outdoors. The article brings up the challenges resisting the spread of 3D Concrete Printing, as the high material cost. Also, it confirms the need for printing standardisation to increase the public’s confidence in this technology.

The second paper by Omar Al Khairat, Hind Zantout and Hassam Chaudhry refers to the significant investment in digital transformation in the Middle East, expected to reach $74 billion by 2026. The authors discuss the values behind using Building Management Systems and Digital Twin for efficient HVAC systems. They also explore the complexities of the HVAC system during its life cycle and propose the Digital Twin tool to Editorial

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optimise the maintenance of this system, causing a reduction in energy consumption and cost.

Community Development

The third article on this theme is for Rana El-Dabaa and Sherif Abdelmohsen, who introduce the Hygromorphic-Thermobimetal Composites (HMTM). This new programmable material can adapt according to the weather’s temperature and humidity. In this material, the wood and metal are laminated together. Interestingly, the article highlights the usefulness of reusing wood as the dead tree releases carbon and reusing it as a wooden product preserves the carbon again.

The authors also take us through 5 years of research in producing the HMTM material implemented in three university workshops.

Under this theme, Fatemeh Mostofi, Vedat Togan and Onur Behzat Tokdemir request to implement machine learning for more reliable construction safety and prediction of accidents. However, they address many challenges, such as the accuracy of the collected data. They suggested two advanced approaches, Generative Adversarial Networks and Autoencoders, to improve the quality of ML-based construction safety solutions in the absence of an adequate input dataset. Besides enhancing site safety, these tools reduce the cost and time of recording and collecting the data. It is noted that these two tools can be used in other scientific areas where the data is limited.

In the final article, Ramez Alchamaa and Zied Dahmani explore the lean construction approach, which becomes a strategy to enhance collaboration and communication with stakeholders for a safer and more organised workplace. The authors urge its application after conventional construction practice has been recorded that 70% of the projects are not completed on budget, besides 61% of the worldwide projects have failed in the delivery time. The paper highlights the importance of creating a Visual Performance Centre (Big Room) for the project teams’ meetings and collaborating in making decisions that save project waste and maximise the value for clients. Moreover, it is encouraged that a daily recorded short meeting (15-20 minutes) is held between the design team and the front-line supervisors to discuss their work commitments.

In the end, the authors bring a successful case study of a project that encountered a delay during COVID-19, which required urgent tailored solutions using lean construction approach, which reduced the delay to less than 1%.

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Editorial

Acknowledgements The Editor would like to sincerely appreciate Charlotte Turner and Monika Toth for their continuous and invaluable help in producing and designing the CES²C Research Bulletin.

Research Bulletin No.8 September 2023

Topic of Focus Positioning Sustainability

Prof. Lynne Jack Director – The Centre of Excellence in Smart and Sustainable Construction Associate Principal (International Research) Director, Institute of Sustainable Built Environment School of Energy, Geoscience, Infrastructure and Society Heriot-Watt University Edinburgh, UK L.B.Jack@hw.ac.uk

With COP28 just around the corner, the excitement and anticipation in Dubai are now palpable as we approach what is, fundamentally, an opportunity for change in the way we address what is often referred to as our ‘climate emergency’. We look to our leaders to collaborate and identify new policies that will see the implementation of significant and transformational change. We look too to technologists, researchers and within our own communities to provide pathways to accelerate change.

Within the Centre of Excellence at Heriot-Watt University, we too seek to identify and implement ways in which we can transition to a low-carbon economy in a sustainable way. Although our core purpose remains unchanged in that we seek to stimulate industry-led innovations and research-driven solutions to address challenges in the Built Environment, we have recently refreshed our strategy for delivery. In recognition of this new approach and a broadening of scope, we have opted to include the word sustainability in our title, and henceforth will be known as CES²C (the Centre of Excellence in Smart and Sustainable Construction).

Within this new operational model for CES²C, we are also keen to ensure connectivity to the wider international community; in part facilitated by the University’s international campuses, but also through direct linkage with other global partners. We have set an ambitious model for growth that will see us work more in tandem with our key partners. In delivering against these goals, we seek to proactively engage with our global University network in deploying the pioneering spirit for which HeriotWatt has come to be known.

As we work collaboratively in our endeavour to deliver research and innovation, it is important to recognise that the challenges we face may be described as ‘wicked problems’, where the complexity of the undertaking can, upon initial analysis, appear entirely intractable. But we must not be deterred and we must also recognise the benefits that collaborative research and innovation can bring. Through the foundation of robust partnerships, we are able, using CES²C as a collaborative platform, to deliver transformation through our project work and via our highly-skilled graduates.

If you would like to know more about the research and innovation work we undertake at Heriot-Watt University or the collaborative opportunities afforded by partnering with CES²C, please feel free to get in touch.

We have also re-cast our key themes of focus; concentrating now on Net Zero; Digital Transformation and Community Development.

Under our Net Zero theme, we seek to help identify multidisciplinary and multi-stakeholder pathways to Net Zero that are data-driven and science-based. The Digital Transformation theme sees us support enhanced productivity, cost savings and risk mitigation. And through our Community Development activities, we place people at the heart of everything we do, working towards providing specialist advice and support to ensure that safety, wellbeing, equality, diversity and inclusivity remain top of the Built Environment agenda.

At CES²C, we seek to accelerate and promote the uptake of innovative solutions for the Built Environment sector. In doing so, we aim to support the UAE in maintaining, indeed growing, its international competitiveness.

Alongside this, we will focus on embedding the requisite knowledge and skills within our graduate cohorts, and on up-skilling the current workforce. The networking and outreach platforms provided by CES²C are key in enabling connectivity across a sector this is wide-reaching and diverse.

The Road to (and beyond) COP28

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Net Zero

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Bio-cementation: pathway towards bringing earthworks a step closer to Net Zero Dr Dimitrios Terzis Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland dimitrios.terzis@epfl.ch

Prof. Lyesse Laloui Swiss Federal Insisute of Technology (EPFL) Lausanne, Switzerland lyesse.laloui@epfl.ch

Despite emerging approximately 15 years ago, the technology of biocementation has yet to be demonstrated in operational environments, raising questions about its cost-competitiveness and environmental performance. This article explores the significance of biocementation in the construction sector’s journey towards achieving Net Zero emissions and emphasizes the critical role of recent pilot-tests in Switzerland towards addressing the uncertainties surrounding the technology’s viability.

Biocementation involves the use of microorganisms to precipitate carbonate minerals within soil or concrete, resulting in enhanced strength and durability.

By harnessing the power of these natural processes, biocementation offers a sustainable alternative to conventional cement-based materials, which are responsible for a substantial portion of global carbon emissions. The application of biocementation can effectively reduce the carbon footprint of construction projects and contribute to the mitigation of both carbon and nitrous oxide emissions which emerge from the sector. Recent field applications in Switzerland have played a crucial role in advancing biocementation technology and provided valuable insights into its efficacy, feasibility, and scalability. We have successfully demonstrated the potential of biocementation in improving the mechanical properties of soil, thereby enabling the construction of more resilient structures.

Moreover, the applications presented herein have helped optimize the process parameters, such as microbial selection, nutrient composition, and environmental conditions, leading to a feasible and scalable industrial solution with certified compatibility with recent environmental norms as well as cost-effectiveness.

The maturation of biocementation has also been facilitated by the development of customized microbial strains with enhanced mineral precipitation capabilities to extend the use of biocementation beyond soil consolidation towards valorizing excavation waste and directly precipitation CO2 into geological formations. In conclusion, as the industry continues to embrace and further develop biocementation, this article summarizes an overview of why the technique represents a vital pathway towards achieving Net Zero emissions in the construction sector.

Keywords: Biocementation, Pilot tests, Quality control, Upscaling, Industry solution, Technology transfer.

1. Introduction

S

oil consolidation plays a crucial role in almost every single civil engineering work, especially when dealing with weak or loose soil conditions. As suitable land for development becomes scarcer and civil infrastructure is hit by intensifying, extreme weather phenomena, soil consolidation emerges as a pressing and all the more relevant measure. In this context, biocementation solutions are emerging offering sustainable and effective approaches to soil consolidation through the use of calcifying and biopolymer-producing bacteria [1][2]. This article highlights the implementation of recent field trials and emphasizes the importance of quality control and assessment in achieving reliable and durable soil bio-consolidation results. It furthers prepares the ground for what’s next towards enhancing the versatility of the solution towards adapting to all types of geologies, including excavation waste with an emphasis on direct CO2 use.

CDW constitutes a significant portion of the non-hazardous solid waste managed by BEEAH. According to statistical records, CDW accounts for approximately 48% of the waste received at BEEAH’s waste management complex in Sharjah, as shown in Table 1. This trend is also reflected in the shared waste statistics paper for Abu Dhabi.

Table 1: Waste Statistics based on Source.

2. Field Trials: Testing Ground for Success The field trials were pivotal in demonstrating the practical application and effectiveness of bio-cementation for soil consolidation. These trials involved collaborating with construction companies, engineering firms, and government agencies to identify suitable sites for implementation. The selected sites represented a variety of soil types and challenging conditions to evaluate the versatility and performance of biocementation.

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2.1 Sandstone cliff stabilization A pilot project took place on a sandstone cliff and its bio-stabilization proved to be a resounding success, employing innovative techniques and advanced technologies. Horizontal boreholes were strategically drilled into the cliff, allowing for precise injections. Through the process of calcite biomineralization, the cliff was strengthened and stabilized. This technique involved the introduction of calcite-forming microorganisms, which facilitated the precipitation of calcite within the sandstone matrix, effectively increasing its density and stability. To ensure the efficacy of the stabilization, rigorous monitoring measures were employed. Seismic monitoring provided real-time data on the behavior of the cliff, allowing for early detection of any potential instability (Figure 1).

Fig. 2 Results from a dynamic penetrometer campaign carried out across a sand (0-4mm) layer of 1.8 meters depth [3].

Fig. 1 P-wave seismic velocity spectra before and after the application of biocementation 2.2 Improving soil bearing capacity This pilot test involved the installation of vertical tubes through a sand layer of approximately 2 m depth and a grain size composition between 0-4 mm, followed by the injection of the bio-strengthening agent. The process allowed for the consolidation of the sand, resulting in improved bearing capacity and stability. To validate the results, a dynamic penetrometer campaign was used to assess the changes in the soil’s mechanical properties, providing a quantitative measure of the technique’s effectiveness. The outcomes of the pilot test were highly encouraging (Figure 2). The dynamic penetrometer measurements revealed a substantial increase in the sand layer’s strength, confirming the successful treatment and enhanced cohesion and friction angle [3].

2.3 Improving the hydromechanical behavior of plastic clays Biocementation offers a promising solution to improve the surface properties of clays and mitigate the adverse effects of desiccation cracking and swelling caused by extreme evaporation and rainfall events, respectively.

Plastic clays are highly susceptible to desiccation cracking when subjected to intense evaporation, leading to the loss of soil integrity and reduced loadbearing capacity. Biocementation introduces bacteria that produce calcium carbonate or other polymers, effectively covering the surface of clay particles and creating a more stable matrix.

Additionally, when heavy rainfall occurs, clays can swell significantly due to the absorption of water, resulting in soil instability and structural damage.

Biocementation combats this by promoting the growth of mineral substances that bind the clay particles together and reducing swelling (Figure 3).

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Fig. 3 Clay matrix prior (left) and after application of biocementation (right)

3. Quality Control and Assessment Quality control and assessment played a significant role in the success of field trials of biocementation. A comprehensive and systematic approach was employed to ensure the reliability and durability of the soil consolidation achieved through bio-cementation. The following aspects were given particular attention: (i) continuous monitoring and sampling of the treated soil were conducted throughout the consolidation process. This allowed for realtime data collection on the progress and effectiveness of the bio-cementation technique. Key parameters such as strength gain, settlement, and durability were measured and analyzed [4]; (ii) laboratory testing of soil samples provided additional insights into the performance of the treated soil. These tests included compressive strength tests, time-dependent assessments, and microscopic analysis to examine the bonding and calcite distribution within the soil matrix [5].

4. Outlook Through Microbially Boosted Carbonate precipitation (MiBOC), an Innovation project supported by the Swiss federal agency for Innovation, Medusoil SA cofounded at EPFL develops the TrinityPrint system as a solution for

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customizable waste management that combines the power of three different soil strains. TrinityPrint utilizes a unique blend of advanced materials and sustainable practices to revolutionize the way we handle excavation waste and promote a circular economy.

Here’s how TrinityPrint works:

structural and environmental benefits such as improved soil resistance, fertility and water quality, respecting recent guidelines according to [6].

As research and development continue, we may witness the widespread adoption of this technology, contributing to a greener and more sustainable future.

The process begins with the collection of different types of excavation waste, mainly fine grained soils. These waste materials are carefully sorted to ensure compatibility with the system. TrinityPrint employs a specialized sorting mechanism to separate the collected waste and adapt its portions for mixing with three distinct microbial soil strains. Each strain corresponds to a particular material type and possesses unique properties necessary for the 3D printing process. Aggregate material is shredded, and transformed into high-quality filament. The system provides extensive design flexibility, allowing users to create a wide range of objects and prototypes. The three strains’ combination enables the production of hybrid structures that harness the strength and characteristics of multiple materials simultaneously. By utilizing waste materials, the process significantly reduces the need for virgin resources and mitigates environmental pollution. It promotes a circular economy by converting waste into valuable products, reducing landfill waste, and minimizing the overall carbon footprint associated with traditional manufacturing.

Fig. 5 Illustration of the combined use of carbon storage and direct mineralization in underground formations enabled by biocementation (source: Medusoil SA)

Conclusion

Fig. 4 Illustration of the combined use of strains for 3D soil printing by TrinityPrint (source Medusoil SA)

The successful implementation of field applications of biocementation underscores the importance of quality control and assessment in achieving reliable and durable results. Through rigorous monitoring, sampling, laboratory testing, and performance evaluation, the projects ensured that the treated soils met the necessary engineering and environmental standards. As bio-cementation gains acceptance, such advances will continue to pave the ground towards promoting the wider adoption of this sustainable and efficient soil consolidation techniques to serve sustainable development.

A next milestone is to test shallow-depth biocementation which allows for easier accessibility, reducing costs and logistical challenges associated with deep geological storage. Additionally, it facilitates enhanced monitoring and control, enabling efficient management of the carbon mineralization process.

By focusing on shallow depths, biocementation demonstrates potential as a viable and sustainable method for long-term carbon storage and mitigating climate change impacts. Harnessing CO2 capture facilities and the power of bacteria to precipitate carbonate minerals in the ground offers a sustainable and potentially long-term solution for carbon sequestration. This approach not only reduces greenhouse gas emissions but also provides additional

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Acknowledgements The authors would like to acknowledge the financial support of the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No. 788587). Author DT would like to thank 102.649 IP-ENG project by Innosuisse for the critical support in the development of MiBOC and TrinityPrint.

References [1]

Terzis, D., 2017. Kinetics, Mechanics and Micro-structure of Bio-cemented Soils EPFL thesis https://doi.org/10.5075/epflthesis-8147

[2]

Terzis, D. and Laloui, L., 2019. A decade of progress and turning points in the understanding of bio-improved soils: A review.

Geomechanics for Energy and the Environment, 19, p.100116.

[3]

Harran, R., Terzis, D. and Laloui, L., 2023. Addressing the challenges of homogeneity, quality control and waste handling in soil bio-cementation: A large-scale experiment. Soils and Foundations, 63(4), p.101332.

[4]

Harran, R., Terzis, D. and Laloui, L., 2022. Characterizing the deformation evolution with stress and time of biocemented sands.

Journal of Geotechnical and Geoenvironmental Engineering, 148(10), p.04022074.

[5]

Terzis, D. and Laloui, L., 2019. Cell-free soil bio-cementation with strength, dilatancy and fabric characterization. Acta Geotechnica, 14, pp.639-656. particularly with respect to recent European norms such as the CEN/TR 17105

[6]

particularly with respect to recent European norms such as the CEN/TR 17105

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Construction and Demolition Waste Recycling at BEEAH Mohammed Sammour Operations Manager Construction and Demolition BEEAH Recycling BEEAH Group Sharjah, UAE msammour@beeahgroup.com

This paper provides an overview of construction and demolition waste, its classification by BEEAH, and focuses on the recycling facility operations of BEEAH. It discusses the historical growth of the recycling facility, the challenges encountered along the way and outlines future development plans.

Keywords: Construciton and Demotion Waste (CDW); recycled crushed aggreage (RCA); BEEAH; Waste management

1. Definition and Statistics

C

DW (Construction and Demolition Waste) is a byproduct of construction, renovation, repair, and demolition projects, comprising various materials such as wood, steel, concrete, gypsum, plastics, metal, asphalt, sand, paper, and cardboard. BEEAH classifies CDW into two categories: mineral C&D and mixed C&D. This classification is determined by the percentage of non-concrete waste in relation to the total volume of delivered waste. If the non-concrete waste volume exceeds 20%, it is classified as mixed C&D. CDW constitutes a significant portion of the non-hazardous solid waste managed by BEEAH. According to statistical records, CDW accounts for approximately 48% of the waste received at BEEAH’s waste management complex in Sharjah, as shown in Table 1. This trend is also reflected in the shared waste statistics paper for Abu Dhabi.

Table 1: Waste Statistics based on Source.

Initially, the facility solely accepted mineral waste, averaging an annual rate of 300,000 tons, while the remaining waste was disposed of in landfills.

In pursuit of BEEAH’s vision of achieving zero waste to landfill, the facility underwent an upgrade in 2015 to enable the recycling of mixed C&D waste. Subsequently, in 2016, the facility expanded its operations to treat all construction and demolition waste generated in Sharjah city, as well as some waste from neighboring emirates. Since then, there has been a 100% diversion of CDW waste from landfills.

2.2 Facility Operations The CDW facility operates in two production shifts and one maintenance shift, with an annual feeding capacity of 650,000 tons. The recovery rate of the process stands at an impressive 97%. The facility employs a combination of manual and machine segregation processes to effectively sort the various types of waste. Subsequently, the concrete waste is crushed and reduced to sizes below 50mm, allowing for further segregation based on size to obtain recycled concrete aggregates (RCA).

2.3 Products The primary product of the CDW facility in Sharjah is RCA. The aggregates are produced using a grading system (Figure 1), with each size being stockpiled and directed towards its designated application. The Sharjah municipality predominantly utilizes all grades of RCA for backfilling purposes. Additionally, the finer course of the aggregate undergoes testing at the construction materials facility to produce interlock, curbstones, hollow blocks, and solid blocks. All samples have been tested and have yielded satisfactory results.

2. Construction and Demolition Waste Facility 2.1 CDW Facility History The facility, established in 2007 through a partnership between Sharjah Municipality and BEEAH, commenced operations in 2009.

In addition to the production of RCA, the CDW facility in Sharjah also focuses on the recovery of recyclable materials from the waste stream, including wood, plastics, and steel. These materials are efficiently segregated and diverted to other specialized facilities for recycling purposes, ensuring their proper and environmentally friendly disposal.

Table 2 records the current production volumes at the CDW facility of BEEAH.

Construction and Demolition Waste Recycling at BEEAH

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recycled road base and sub-base. Notably, in 2023, BEEAH has successfully delivered over 100,000 tons of recycled road base for the Etihad Rail construction project.

These initiatives demonstrate BEEAH’s commitment to promoting the use of sustainable and certified materials in road construction, fostering partnerships with government entities, and driving the adoption of recycled materials in infrastructure projects.

4. Future growth

Fig. 1 Sorting RCA at BEEAH and its sizes

As BEEAH continues to grow and expand its operations across the UAE and the Gulf region, the CDW recycling efforts will be extended to encompass the cities and countries where Bee’ah operates. The recycling process itself is undergoing continuous upgrades to enable further recycling capabilities and the creation of additional final products, including construction materials. One crucial development is the production of Solid Recovered Fuel (SRF), which will significantly enhance the recovery rate, aiming to reach an impressive 99.9%. These advancements highlight BEEAHs commitment to advancing sustainable practices and maximizing resource recovery throughout its expanding operations.

Table 2: Production volumes at the CDW facility.

Conclusions BEEAH operates as an environmental solution provider, and its CDW recycling initiatives have successfully addressed approximately 50% of waste dumping in landfills. This sustainable and economically viable approach has significantly reduced the environmental impact associated with waste disposal while promoting resource conservation and circular economy principles.

References [1]

3. Challenges and Market One of the main challenges faced by BEEAH was the market acceptance of RCA and the need to demonstrate its reliability and consistent quality.

This challenge stemmed from the fact that RCA is derived from a nonhomogeneous feedstock waste stream, which can vary in composition over time. Initially, the majority of RCA produced was utilized by the Sharjah Municipality for backfilling, with only 5% being used by the private sector in construction projects. To address this challenge, BEEAH focused on upgrading their recycling line to accommodate all types of CDW and implemented processes to ensure consistent quality of the RCA. In 2022, BEEAH entered into a partnership with the Ministry of Energy and Infrastructure, participating in ministry construction projects by supplying recycled road base to replace 30% of virgin road base in the construction of new roads, such as Sheikh Mohammed Bin Zayed Road in Ajman and Al Tella Bridge. BEEAH has also collaborated with the Road Transportation Authority to ensure the verification and certification of recycled road base as safe and suitable materials for road construction, a process that has already been achieved in Abu Dhabi with the acquisition of the ADQCC certificate for

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Waste Statistics 2019 Annual Yearly en.pdf. Non-hazardous solid waste generation by source activity. https://www.scad.gov.ae.

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The State of Circularity in Dubai Faisal Ali Al Rashid Senior Director Demand Side Management Dubai Supreme Council of Energy Dubai, UAE FaisalR@dubaisce.gov.ae

Majd Fayyad DSM Strategy & Policy Lead Demand Side Management Dubai Supreme Council of Energy Dubai, UAE majd.fayyad@dubaisce.gov.ae

Yitong Lin Dubai Business Associate Intern with Dubai Supreme Council of Energy Dubai, UAE yitong.lin@dubaisce.gov.ae

Circular Economy (CE) is attracting growing attention as the world seeks more sustainable economic development. To accelerate Dubai’s transition into a more circular economy, the Dubai Supreme Council of Energy (DSCE) established the Circular Economy Committee in 2021 and published its first CE Report in 2023.

This paper starts by introducing Circular Economy, followed by highlighting the key measurement indicators at different levels, including the country level and the business level. The article benchmarked global CE practices and studied further China’s Circular Economy Promotion Law and European Union’s Circular Economy Action Plan. It proceeds to describe the state of circularity in Dubai and the motivation for launching the DSCE CE Committee. As for existing projects, DSCE Demand Side Management (DSM) Strategy promotes several initiatives that align with CE principles, such as promoting energy-efficient buildings, retrofitting existing building stock, and efficient cooling technologies. DSCE CE Committee also engaged with multiple entities from the public and private sectors that implement CE projects to gain a better understanding of the current state of circularity in Dubai. In general, Dubai’s CE market is still at an early stage with many benefits to unlock. DSCE developed and fully activated the CE implementation plan for 2023-2024, which includes several initiatives across different entities. It is vital for different sectors to work together to advance circularity, especially with COP28 being just around the corner.

Keywords: Circular Economy, Energy, Resources, Policy, Strategy, Dubai

1. Introduction

2. Measurement

ubai’s economy has grown substantially over the past decades, becoming one of the global hubs where people from all over the world live and prosper. Consequently, it is evident that the Emirate would naturally require substantial energy and resources to sustain its continued economic development. A circular economy transforms the traditional takemake-waste linear development into a more environmentally friendly mode, ultimately aiming to decouple economic growth from the consumption of limited resources. According to the Ellen MacArthur Foundation, there are three basic principles of a Circular Economy: 1) Eliminate waste and pollution; 2) Circulate products and materials; 3) Regenerate Nature [1].

A circular economy is a broad concept involving numerous stakeholders, as such it is relevant to define goals based on different levels: namely macro, meso, micro, and nano levels [3]. Macro and meso levels measure the performance of countries, cities, and industries, whereas the latter two evaluate the circularity of companies, products, and components. Establishing indicators and targets to monitor the progress of CE initiatives is crucial for enhancing the level of ambition and effectively implementing identified policies and strategies.

To support and accelerate CE transition, the Dubai Supreme Council of Energy (DSCE) established the CE Committee in 2021, aiming to bring both public and private sectors to join this endeavour [2]. A circular economy will not only contribute to combating conservation challenges but also bring more quality and sustainable ways of living to all residents in Dubai and the UAE.

UAE launched its Circular Economy Policy in 2021 and provided a comprehensive framework for CE transition. The UAE CE Policy also outlines several key areas of indicators to measure circularity, including economic performance, renewable energy and GHG emissions, resource productivity, and waste generation [4].

The DSCE CE Committee aims to: 1) Develop and launch innovative tools, measuring means, initiatives, and policies to promote circularity; 2) Support start-ups and develop the capabilities of entrepreneurs in the sector: 3) Encourage the utilization of modern technologies capabilities; 4) Enhance the efficiency of natural resources and promote sustainable best practices.

2.2 Measuring Circularity on Business Level

D

2.1 Measuring Circularity on Country Level

Several tools can be utilized to measure the circularity of businesses, including Circulytics developed by the Ellen MacArthur Foundation, Circular Transition Indicators by the World Business Council for Sustainable Development The State of Circularity in Dubai

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(WBCSD), and Circularity Check by Ecopreneur [6][7][8].

Given the different stages of maturity, WBCSD also proposes three levels of metrics for companies to measure their CE performance [3]. Operational Efficiency Metrics measure standard indicators such as resource efficiency and energy consumption, whereas Sustainability Performance Metrics and Circular Value Creation Metrics pursue further in the value chain and measure additional factors and initiatives.

3. Global Benchmarking

aims to ensure resources used are kept in the EU economy for as long as possible. The monitoring framework has multiple indicators, including EU selfsufficiency for raw materials, green public procurement, waste generation, recycling rates, trade in recyclable raw materials, investments, jobs, and patents on CE.

4. The State of Circularity in Dubai 4.1 Development of Policy Framework for CE Transition

and

Management

Many countries have initiated and developed CE-related policies, dating back to the 1990s in Germany and Japan, and more recently in European Commission’s Circular Economy Action Plan. Practices in China and EU are further studied for Dubai’s Circular Economy development [5].

The motivation to launch a DSCE circular economy initiative comes from a broad overview of the challenges and opportunities of CE transition. The overview is based on stakeholder engagement conducted by DSCE, and information received from different entities, including Dubai Department of Economy and Tourism [5][13]:

Table 1: Global CE Policy Leadership

Table 2: Challenges and Opportunities of CE Transition

3.1 China China has published several laws since 2002, most notably the Circular Economy Promotion Law of 2009 and later revised in 2018, where they pointed out that CE strategies will be implemented only if it is viable in technology, economy, and suitable for protecting the environment [9].

As for measurement indicators, China adopts an altered version of the European Union’s (EU) material flow analysis (MFA), whose measurement can range from whole cities to single rivers. The system categorizes data into four categories: Resource output, resource consumption, integrated resource utilization, and reduction in waste generation [10][11].

3.2 European Union The new Circular Economy Action Plan was adopted by the European Commission in 2020 [12]. The new plan looks at the entire life cycle of products, promotes circular economy processes, fosters sustainable consumption, and

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The State of Circularity in Dubai

Moreover, CE principles have great synergy with the broader government policy framework of Dubai. The principles also align very well with existing strategic and policy framework within DSCE, including Demand Side Management Strategy, Integrated Water Resource Management Strategy, and Green Mobility Strategy. As such, DSCE can capitalize on established knowledge of developing and monitoring strategies to ensure effective and efficient CE transition. As a result, DSCE established the Circular Economy Committee to promote CE initiatives across different sectors within the emirate in 2021 [2].

4.2 Development of Policy Framework for CE Transition

and

Management

DSCE Demand Side Management Strategy oversees several key programs that align well with CE principles. For buildings and infrastructure, DSM aims to: 1) increase energy and water efficiency in new buildings through building regulations and compliance; 2) Retrofitting existing building stock & infrastructure with electricity & water efficiency measures; 3) Adopt high-

Research Bulletin No.8 September 2023

efficiency lighting in public spaces in Dubai; 4) Promoting efficient cooling technology use in Dubai buildings including district.

Moreover, the DSM strategy also promotes the adoption and compliance with Minimum Energy Performance Standards and labels for air conditioners, home appliances and industry equipment, as well as building-level solar energy systems. On the water level, the Integrated Water Resource Management strategy aims to increase recycled water use and reduce desalination.

DSCE also engages with multiple entities to promote CE transition. These entities are from governmental organizations, energy and facility management companies, transportation and logistics companies, environmental groups and academic institutions, real estate development, and consumer goods companies. DSCE CE Committee conducted a data collection exercise of their ongoing CE initiatives and actions and mapped them against the three basic principles of CE from the Ellen MacArthur Foundation [5].

The results indicate relatively abundant efforts related to Ellen MacArthur Foundation’s Principle 1. Examples of such initiatives are highlighted in Table 3.

Table 3: Examples of CE initiatives in Dubai

Compared to actions under Principle 1, initiatives under Principle 2, circulate products and materials, are relatively still at the development stage. This is one of the areas where future actions can be taken to accelerate CE transition.

5. Future Planning of DSCE CE Committee Dubai, in general, is still at an early stage of an integrated CE strategy, facing challenges to reap the full benefits of a circular economy. Looking forward, coordinated actions across Dubai government entities and the private sector would be needed to unlock further CE benefits. Based on engagement with DSCE CE Committee members and industry stakeholders, DSCE developed the implementation plan for 2023-2024. The finalized plan span across 7 key categories: 1) Policies & regulations; 2) Procurement & infrastructure; 3) Education & awareness; 4) DEWA projects; 5) Leadership & collaboration; 6) Incentives; 7) Awards.

Upon effective implementation, DSCE envisions the emirate substantially increasing its overall sustainability status and its attractiveness to international ESG investment. Circular Economy represents one of Dubai’s greatest environmental and economic opportunities, especially with COP28 being just around the corner. It is vital for different sectors and entities in Dubai to join this transition, and to collectively establish and advance Dubai’s transition towards circular economy.

References [1]

Ellen MacArthur Foundation, 2023. Circular Economy Introduction, available at: https://ellenmacarthurfoundation.org/topics/circulareconomy-introduction/overview (accessed: July 9, 2023).

[2]

Dubai Media Office, 2021. Dubai Supreme Council of Energy launches Circular Economy Committee to promote circular economy across different sectors in Dubai, available at: https:// www.mediaoffice.ae/en/news/2021/October/15-10/DubaiSupreme-Council-of-Energy-launches-Circular-EconomyCommittee (accessed: July 9, 2023).

[3]

World Business Council for Sustainable Development, 2018.

Circular Metrics Landscape Analysis, available at: https://www. wbcsd.org/contentwbc/download/5065/66731/1 (accessed: July 9, 2023).

[4]

UAE Ministry of Climate Change and Environment, et al., 2021.

UAE Circular Economy Policy 2021-2031, available at: https:// www.moccae.gov.ae/assets/download/d15b52b/UAE%20 Circular%20Economy%20Policy.pdf.aspx (accessed: July 9, 2023).

[5]

Dubai Supreme Council of Energy, 2022. DSCE Circular Economy 2022 Report: Enabling a circular economy transition through energy, water, transport and waste management, available at https://dubaisce.gov.ae/en/dsce-circular-economy-initiative/ (accessed: July 9, 2023).

[6]

Ellen MacArthur Foundation, 2023. Measure business circularity: Circulytics, available at: https://ellenmacarthurfoundation.org/ resources/circulytics/overview (accessed: July 9, 2023).

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References [7]

World Business Council for Sustainable Development, 2023.

Circular Transition Indicators (CTI), available at: https://www. wbcsd.org/Programs/Circular-Economy/Metrics-Measurement/ Circular-transition-indicators (accessed: July 9, 2023).

[8]

Ecopreneur, 2023. Circularity Check, available at: https:// ecopreneur.eu/circularity-check-landing-page/ (accessed: July 9, 2023).

[9]

United Nations Environmental Programme, 2018. Circular Economy Promotion Law of the People’s Republic of China, available at https://leap.unep.org/countries/cn/nationallegislation/circular-economy-promotion-law-peoples-republicchina (accessed: July 9, 2023).

[10]

OECD, 2008. Measuring material flows and resource productivity, available at https://www.oecd.org/environment/indicatorsmodelling-outlooks/MFA-Guide.pdf (accessed: July 9, 2023).

[11] Geng Y., Fu J., Sarkis J., Xue B., 2011. Towards a national circular economy indicator system in China: an evaluation and critical analysis, Journal of Cleaner Production, Pages 216-224, Volume 23, Issue 1. DOI:10.1016/j.jclepro.2011.07.005 [12]

European Commission, 2020. Circular Economy Action Plan, available at: https://environment.ec.europa.eu/strategy/circulareconomy-action-plan_en (accessed: July 9, 2023).

[13] Dubai Department of Economic Development, 2020. Dubai Economy sharpens focus on Circular Economy in preparation for next 50 years, available at: https://ded.ae/news/en/key_ news/4643 (accessed: July 9, 2023).

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Research Bulletin Research Bulletin No.8 September 2023 No.8 September 2023

Ways to Incorporate Sustainable Development in the Construction Practice Dr Cheng Siew Goh Assistant Professor Northumbria University Newcastle, UK

The application of sustainable development in construction requires multidisciplinary and interdisciplinary efforts to address complex management issues.

Extensive up-front planning and communication across the project team are essential. Proper adjustments shall be made to the traditional management practices to optimize the delivery of sustainability practices in construction. To address these gaps, the author published two works recently to highlight the importance of using innovative project management approaches for the delivery of sustainable construction projects. The published works include a journal article titled “Exploring Economic Impacts of Sustainable Construction Projects on Stakeholders: The Role of Integrated Project Delivery” published in the Journal of Legal Affairs and Dispute Resolution in Engineering and Construction, and a book chapter titled “Management” in Sustainable Construction Technologies published by Butterworth-Heinemann. In these two publications, Integrated Project Delivery (IPD) and sustainable procurement were proposed. With reference to the mentioned publications, this paper discusses how IPD and sustainable procurement can offer a more robust solution to promote seamless coordination and close collaboration among various project stakeholders. Both IPD and sustainable procurement offer a good mechanism that fosters full accountability and involvement of all key stakeholders for a wider implementation of sustainable development in construction.

Keywords: Sustainable Construction; Sustainable Development; Management; Integrted Project Delivery; Sustainabel Procurement; Construction Stakeholders.

1. Definition and Statistics

S

ustainable construction is the incorporation of sustainable development principles into building and construction practice in the entire project life cycle phases, from planning, design, construction, operation, and demolition, to decommissioning of the built assets [1]. Numerous stakeholders can influence and are influenced by a sustainable construction project, from the top of the supply chain - project clients down to end users. Developers, clients, and end users are key decision makers in the sustainable building supply and demand but there has been a mismatch of cost and benefits to be encountered among the stakeholders [2]. The presence of numerous stakeholders in sustainable construction may result in split incentives and principal-agent problems [3]. It is crucial to reach a consensus among all stakeholders about the feasibility of sustainable construction practices to boost its application in the market.

Implementing sustainable development is more efficient and effective at the strategic level, rather than at the operation level of a construction business [1]. The application of sustainable development in construction requires multidisciplinary and interdisciplinary efforts to address complex management issues such as stakeholders’ attitudes, supply chain deficiencies, poor coordination and collaboration among stakeholders, and discouragement of existing systems [4]. Extensive up-front planning and communication across the project team are essential [5]. Sustainable construction projects also call for cross-discipline coordination on site selections, construction materials and techniques, building systems and subsystems, as well as commissioning and decommissioning of sustainable built assets.

Sustainable construction projects are different in nature as compared to traditional construction projects in terms of the delivery of technical knowledge and management [5]. Proper adjustments shall therefore be made to the traditional management practices to optimize the delivery of sustainability practices in construction [6]. Traditional construction management approaches that are often linear and fragmented do not support sustainable construction deliverables in an efficient manner. In addition, the traditional unit cost model does not offer enough flexibility to account for life cycle costing or assembling different combinations of professionals to accommodate the project’s specific skills and service needs for sustainability [6]. To address these gaps, the author published two works recently to highlight the importance of using innovative project management approaches for the delivery of sustainable construction projects. The mentioned publications are a journal article, “Exploring Economic Impacts of Sustainable Construction Projects on Stakeholders: The Role of Integrated Project Delivery”, published in the Journal of Legal Affairs and Dispute Resolution in Engineering and Construction and a book chapter titled “Management” in Sustainable Construction Technologies published by Butterworth-Heinemann.

The purpose of this article is to describe the recent research works undertaken by the author in exploring suitable management approaches for adopting sustainable construction. Two project management approaches were proposed: integrated project delivery and sustainable procurement.

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2. Management Approaches for Sustainable Construction 2.1 Integrated Project Delivery (IPD) In sustainable construction projects, tremendous efforts are required to ensure sustainability principles are well embedded in the building systems.

However, the linear process in the conventional management approach does not allow close collaboration and seamless coordination amongst the key project stakeholders.

Integrated Project Delivery (IPD) is an innovative collaborative approach to construction project delivery by integrating people, systems, business structure and practices into a process for collaboration. In IPD, various project parties such as owner, design teams, users, contractors and subcontractors are involved starting from the project brief, pre-design, design to the construction, and commissioning stage. The project owner sets sustainable goals and priorities at the project onset and establishes a framework that guides the project team in meeting the goals. The project team then work collaboratively in defining the sustainability goals for the project. Because IPD put the project team members together in the project’s early stage, long-term support from the involved stakeholders toward sustainable development goals can be cultivated. As compared to the conventional practice that involves the key project team members in a chronological phase, IPD does not preclude builders or design professionals in the decision-making for the sustainable site line items such as transportation, open spaces site context, building orientations, community connectivity, etc.

IPD emphasizes connections and improves communications among stakeholders throughout the project phases. With IPD, a “new team” can be formed from stakeholders who traditionally work as separate entities. More time and energy are invested upfront early in the design phase to allow maximum flexibility in the delivery of sustainable projects [7].

The work principles of IPD offer an enabling environment to develop sustainable construction projects by streamlining the flow of information and project workflows. Due to the interconnectedness of sustainable building design components, design professionals, builders, and other team members need to work along with each other during the project inception stage to maximise sustainable practices at the most efficient cost [6]. Stakeholder partnerships in IPD can also foster buy-in, which is crucial for a sustainable construction project that cannot afford to absorb changes, cost increases or delays in the subsequent process [6].

organisations meet their needs for goods, services, works and utilities in a way that achieves value for money on a whole life cycle basis in terms of generating benefits not only to the organisation but also to society and economy, whilst significantly reducing negative impacts on the environment” [9].

Sustainable procurement is an enabler to embed sustainability in governance processes across an organization as well as throughout the whole supply chains. It gives active and visible leadership to organizations in managing internal operations and external practices with influences on their associated suppliers and external stakeholders. The stance and expectation of an organization on sustainability are communicated clearly to stakeholders which in turn lead to more effective engagement [10]. Sustainable procurement could offer a well-suited mechanism for sustainable construction initiatives.

More efforts should therefore be made to increase industry’s acceptance of sustainable procurement.

Conclusions This paper introduces the use of two management approaches in construction organizations to optimise the delivery of sustainable development in construction. The proposed management approaches are Integrated Project Delivery (IPD) and sustainable procurement. By adopting appropriate project management approaches such as IPD and sustainable procurement, the project team can develop a more holistic view in gauging the underlying environmental, social and economic values of sustainable construction projects from a whole life cycle perspective.

The traditional management approaches that are fragmented and linear do not have a good capability to support the collaborative environments required by a sustainable construction project. The mentioned management approaches can help address the gaps in sustainable construction practice by offering a more robust sustainable solution with full accountability and involvement of all key stakeholders.

Acknowledgements Acknowledgments are given to Heriot-Watt University Recovery Fund to support the publication of the research work.

2.2 Sustainable Procurement Procurement is a key construction management process in which it governs contractual agreements, technical performance systems, culture, procedures, environmental sustainability, organization, conflicts, and building economies [8]. Therefore, procurement offers great potential to improve the sustainable performance of construction practices. Selecting an appropriate procurement approach is significant to integrate sustainability into construction and its operation. To work toward sustainability goals, sustainability requirements should be embedded in the supply chain and contract documents of construction practice.

References [1]

Goh, C. S. 2019. Management. In Sustainable Construction Technologies, 93-105, Butterworth-Heinemann.

[2]

Deng, Y. and Wu, J., 2014. Economic returns to residential green building investment: The developers’ perspective. Regional Science and Urban Economics, 47, pp.35-44.

Sustainability goals shall be incorporated into procurement and contract documents since the beginning to avoid undesirable modifications to the projects. Sustainable procurement is defined as “a process whereby public

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[3]

Zhang, L., J. Wu, and H. Liu. 2018. “Turning green into gold: A review on the economics of green buildings.” J. Cleaner Prod. 172 (Jan): 2234–2245. https://doi.org/10.1016/j. jclepro.2017.11.188.

[4]

Goh, C.S. (2014). Development of a capability maturity model for sustainable construction. HKU Theses Online (HKUTO).

[5]

Goh, C. S., Su, F., & Rowlinson, S. (2023). Exploring Economic Impacts of Sustainable Construction Projects on Stakeholders: The Role of Integrated Project Delivery. Journal of Legal Affairs and Dispute Resolution in Engineering and Construction, 15(3), 04523026

[6]

Robichaud, L. B., and V. S. Anantatmula. 2011. Greening project management practices for sustainable construction. Journal of Management in Engineering 27 (1): 48–57. https://doi. org/10.1061/(ASCE)ME.1943-5479.0000030

[7]

USGBC (2014). Green Building 101: What Is an Integrated Process? Available at http://www.usgbc.org/articles/greenbuilding-101-what-integrated-process..

[8]

Rowlinson, S., McDermott, P. (Eds.), 2005. Procurement Systems: A Guide to Best Practice in AU:35 Construction. Routledge, London, United Kingdom.

[9]

UNEP, 2012. Sustainable Public Procurement Implementation Guidelines: Introducing UNEP’s Approach. UNEP, Paris.

[10] Goodhew, S., 2016. Sustainable construction processes: A resource text. John Wiley & Sons, Chichester, UK.

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Hot Weather Concreting: Challenges and Current Practices Dr Samer Al Martini Associate Professor Department of Civil Engineering Abu Dhabi University Abu Dhabi, UAE samer.almartini@adu.ac.ae

Dr Reem Sabouni Associate Professor Department of Civil Engineering Abu Dhabi University Abu Dhabi, UAE reem.sabouni@adu.ac.ae

The objective of this paper is to explore the challenges that face concrete under hot weather conditions. The effects of hot weather on the fresh and mechanical properties of concrete are presented. The paper presents some of the practices taken to mitigate the effects of hot weather on concrete.

Keywords: Concrete, high temperature, compressive strength, slump loss.

1. Introduction

2. Hot weather concreting challenges

ot weather conditions can significantly impact the quality of both fresh and hardened properties of concrete, primarily due to accelerated water evaporation and cement hydration rates [1].

Various industry standards and guidelines have been established to define a threshold for job site temperatures, beyond which concrete construction is considered to be carried out under hot weather conditions. For example, The American Concrete Institute’s “Specification for Hot Weather Concreting” sets an upper limit of 27°C for ambient temperature during the production of highquality concrete [2]. The American Society for Testing and Materials (ASTM) also specifies that concrete mixing and initial curing should not exceed 27°C [3].

2.1 Cement Hydration

H

Adhering strictly to these temperature limits presents challenges in practice, as it demands several precautions that can be difficult to implement on-site without incurring additional high costs. Furthermore, designing concrete mixtures becomes a complex task, as multiple interacting factors come into play, including the selection of concrete ingredients, proper placement, compaction, curing techniques, and the specific conditions of the construction site.

In many hot weather countries, the temperature during a typical summer day often exceeds the recommended specifications mentioned above. For instance, studies have shown that in the vicinity of Dhahran, located in eastern Saudi Arabia, the summer daytime temperature frequently exceeds 40°C [1].

To address the potential effects of hot weather on concrete, the ACI Committee 305 for Hot Weather Concreting recommends conducting trial batches at the highest expected job site temperature during the concrete mixture design phase to assess and mitigate hot weather effects [4]. This proactive approach helps in evaluating the concrete’s performance and allows for necessary adjustments to ensure the desired quality even in challenging environmental conditions.

20 Hot Weather Concreting

As previously discussed, the addition of extra water is necessary at high temperatures to compensate for rapid evaporation. However, this practice leads to a higher water-to-cement ratio (w/c). Concrete placed under high temperatures typically exhibits lower 28-day compressive strength compared to concrete placed under moderate temperatures. Several factors contribute to this outcome, including the higher w/c, elevated concrete temperature during placement or curing, or a combination of both [4].

Researchers such as Al Gahtani et al. [1] have observed that concrete specimens prepared at a normal laboratory temperature but subjected to high-temperature curing exhibited compressive strengths approximately 6-20% lower than those prepared and cured at normal temperatures. The adverse effects on concrete strength stem from the accelerated hydration at early ages when cured at high temperatures [5]. High curing temperatures result in a protective coating on the surface of hydrated cement grains, hindering subsequent hydration and leading to a non-uniform distribution of hydration products within the hardened cement paste matrix, ultimately reducing compressive strength [6-8].

Gaynor et al. [9] also investigated the impact of initial curing on concrete compressive strength. They exposed some concrete specimens to an initial air-curing process at 38°C for 16-20 hours, followed by further moist curing at 23°C and 95% relative humidity, simulating poor initial curing conditions in hot weather. Compared to specimens solely cured in a moist curing room, the 28-day compressive strength of those initially cured at 38°C was approximately 11% lower. These findings underscore the importance of proper curing practices, especially in hot weather conditions, to ensure optimal concrete strength and performance.

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2.2 Slump Loss and Setting In hot weather regions, the rapid evaporation of water and accelerated cement hydration are the primary factors responsible for the swift stiffening of fresh concrete. Sorka and Ravina [6] found that a temperature increase from 20–40°C led to approximately 2.5 times faster cement hydration, resulting in rapid slump loss of the concrete. The hot weather was reported to negatively affect the slump and rheological properties of flowable concrete. The slump retention has significantly dropped with higher temperature, while both yield stress and plastic viscosity increased [10].

El-Rayyes [8] conducted a study on the effect of ambient air temperature on the initial and final setting times of concrete mixtures with varying water-tocement ratios (w/c) in extremely hot climates. The w/c ratios ranged from 0.35–0.70, and the concrete mixtures were initially prepared in a laboratory at a controlled temperature of 23°C. After mixing, mortar was sieved from each mixture, and its initial and final setting times were measured in the lab at 23°C and outdoors at ambient temperatures ranging from 36–41°C. The results showed that the temperature increase from 23–41°C reduced the initial and final setting times of concrete by approximately 25%.

2.3 Decreased Compressive Strength (28 day) As previously mentioned, additional water is necessary at high temperatures to compensate for rapid evaporation. However, this results in a higher waterto-cement ratio (w/c). Concrete placed under high temperatures exhibits a lower 28-day compressive strength compared to that placed under moderate temperatures. This decrease in strength can be attributed to the higher w/c, elevated concrete temperature at the time of placement or during curing, or a combination of both [4].

Al Martini and Nehdi [11] reported that the early strength compressive strength increased at higher temperature while the 28 day compressive strength decreased.

Al Gahtani et al. [1] conducted research showing that the compressive strength of concrete specimens prepared at a normal laboratory temperature but cured under high temperature was approximately 6–20% lower than that of corresponding specimens prepared and cured at a normal temperature.

They explained these results by pointing out that the acceleration of hydration at early ages during high-temperature curing adversely affects concrete strength. The high curing temperature forms a protective coating on the surface of hydrated cement grains, hindering subsequent hydration and leading to a non-uniform distribution of hydration products within the hardened cement paste matrix, ultimately resulting in reduced compressive strength [1].

Gaynor et al. [9] investigated the impact of initial curing on concrete’s compressive strength. They air-cured some concrete specimens for 16–20 hours at a temperature of 38°C and then transferred them to a moist curing room at 23°C with 95% relative humidity. In comparison, other specimens were solely cured in the moist curing room. This initial curing process aimed to simulate poor curing conditions for fresh concrete in hot weather. Their results demonstrated that the 28-day compressive strength of specimens initially cured at 38°C was about 11% lower than that of specimens initially cured solely in the moist curing room.

3. Practices for Mitigating Hot Weather Concreting Problems To mitigate the detrimental impact of hot weather on concrete, it is advisable to schedule concrete placement during periods of lower temperatures that comply with acceptable standards. However, adhering to this recommendation may not always be feasible, particularly for large projects with tight schedules that require continuous concreting work, even during high-temperature periods. In such situations, specific practices are employed for hot weather concreting, including: 3.1 Using Cooled Mixing Water Although water constitutes the least mass in concrete mixing compared to aggregates or cement, using cooled water can still have a notable impact on reducing the overall concrete temperature, though the reduction may not be significant. For instance, lowering the mixing water’s temperature by 2°C can lead to an approximate 0.5°C reduction in the concrete temperature [4].

The ACI 305R–99 report outlines the expected decrease in concrete temperature when replacing a portion of the mixing water, which initially has temperatures of 16°C, 21°C, 27°C, or 32°C, with cooled water at 7°C. The report highlights that the greater the amount of cooled water incorporated as part of the mixing water, the more pronounced the reduction in concrete temperature. Furthermore, a larger temperature difference between the cooled water (7°C) and the regular mixing water contributes to a more substantial reduction in the concrete temperature.

3.2 Using Ice as Partial Replacement for Mixing Water The utilization of ice as part of the mixing water has proven to be a significant method for reducing the temperature of fresh concrete [4]. Crushed ice is introduced into the concrete mixer as a component of the mixing water, but its proportion should not exceed 75% of the total mixing water required.

The greater the amount of ice added as part of the mixing water, the more substantial the reduction in the fresh concrete temperature achieved [4].

According to the ACI report, replacing 75% of the mixing water with ice can lower the concrete temperature to approximately 20–23°C. This demonstrates that this approach is more effective than using cooled water alone. However, it is worth noting that implementing this practice can be costly, as it necessitates the installation of additional equipment at ready mix concrete plants [4].

3.3 Using Proper Ingredients Proper selection of concrete ingredients is crucial to ensure satisfactory performance in hot weather conditions. To reduce the internal concrete temperature during hydration, it is advisable to keep the cement content as low as possible while meeting the requirements for workability, strength, and durability. In hot weather, supplementary cementitious materials like fly ash or blast furnace slag are often used to partially replace Portland cement.

These materials have been shown to decrease the early rate of heat evolution, thereby better controlling the rise in concrete temperature and the rate of slump loss.

Hot Weather Concreting

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Given that aggregates make up a substantial 60–70% of the total concrete volume, their temperature significantly impacts the fresh concrete temperature.

For instance, when aggregates’ temperature increases from 16°C to 32°C, the concrete temperature rises by approximately 17°C [4]. Therefore, it is essential to employ practical measures to keep the aggregates as cool as possible, such as storing them in shaded areas.

materials while reducing the water-to-cement ratio. However, it’s important to note that these superplasticizers are typically developed in regions with milder temperatures, and their performance when incorporated in concrete at high temperatures is not yet fully understood. Thus, a superplasticizer that works well in concrete under mild temperature conditions may yield disappointing results when used in hot weather.

3.4 Using chemical admixtures

Superplasticizers are typically added to cement-based materials to improve their flow in their fresh state by deflocculating the particles. Nonetheless, extensive research is required to develop a thorough understanding of how to effectively utilize superplasticizers in hot weather concreting. Gaining fundamental knowledge in this area is essential to address the specific challenges presented by hot weather conditions and optimize the use of superplasticizers in such scenarios.

Chemical admixtures are commonly added to concrete to reduce the amount of mixing water while maintaining suitable workability [12]. ASTM C494 recognizes various types of admixtures, such as water-reducing admixtures (Type A), retarding admixtures (Type B), accelerating admixtures (Type C), water-reducing and retarding admixtures (Type D), and water-reducing and accelerating admixtures (Type E). Water-reducing admixtures typically reduce the required mixing water for concrete with given workability by 5–15%. On the other hand, high-range water-reducing admixtures, also known as superplasticizers, can reduce the mixing water content by up to 30%.

Researchers reported that chemical admixtures should be carefully added to concrete under hot weather. Al Martini and Nehdi [13] reported that polycaboxylate high range water reducing and retarding admixtures showed adverse effects on rheological properties of concrete under hot weather conditions when their dosages exceeded the saturation dosage. Al Martini and Al Khatib [14] documented that melamine based high range water reducing admixtures are recommended to be used close to their saturation to ensure adequate rheological properties under hot weather. Al Martini and Al Khatib [15] recommended not to use overdosed chemical admixtures with self-consolidating concrete, as this will significantly reduce both compressive strength and flexural strength.

Super-plasticizers are especially utilized to create “self-consolidating concrete (SCC),” a highly flowable concrete that can fill formwork effectively without the need for vibration. SCC is beneficial for placing concrete in thin and heavily reinforced sections. In hot weather environments, using concrete with high flowability like SCC can help counteract the adverse effects of high temperature on slump loss [16]. Super-plasticizers significantly increase the initial slump of concrete, thus compensating for subsequent slump loss, which is particularly valuable in hot weather conditions.

However, it’s important to note that these admixtures are often developed in countries with milder climates, and their performance may vary when used in hot climates. Therefore, it is essential to subject such admixtures to testing under high-temperature conditions before recommending them for hot weather concreting.

4. Summary and Conclusions Hot weather can pose challenges for concrete, affecting its mixing, placement, and curing processes, which in turn can impact the properties of both fresh and hardened concrete. The main issues arise from accelerated cement hydration and rapid evaporation of mixing water at high temperatures. Current practices to tackle hot weather concreting problems, such as adding cooled water or ice to the mixing water, may not offer optimal solutions.

Superplasticizers hold promise as potential remedies for hot weather concreting problems, as they can enhance the workability of cement-based

22 Hot Weather Concreting

References [1]

Al-Gahtani H.J., Abassi A.G., AlAmoudi S.B. Concrete mixture design for hot weather: experimental and statistical analysis.

Magazine of Concrete Research. 1998; 50(2): 95– 105p.

[2]

ACI COMMITTEE 305.1–06. Specification for hot weather concreting. ACI Standards. American Concrete Institute, Farmington Hills: MI; 2007; 1–12p.

[3]

ASTM C 31. Standard practice for making and curing concrete test specimens in the field. Annual book of the American society for testing and materials. West Conshohocken: PA. 2002; 4.02.

[4]

ACI COMMITTEE 305R–99. Hot weather concreting. ACI Manual of Concrete Practice American Concrete Institute. Farmington Hills: MI; 1999; 1–20p.

[5]

Hewlett P.C. Lea’s chemistry cement and concrete. 4th Edn. New York; Toronto: John Wiley & Sons Inc.; 1998; 241–89p.

[6]

Soroka I., Ravina D. Hot weather concreting with admixtures.

Cement and Concrete Composites. 1998; 20(4): 129–136p.

[7]

Hasanain G.S., Khalaf T.A., Mahmood K. Water evaporation from freshly placed concrete surfaces in hot weather. Cement and Concrete Research, 1989; 19(3): 465–75p.

[8]

El-Rayyes M.S. Remedies to rapid setting in hot weather concreting. In Proc. RILEM Symposium. Admixtures for Concrete.

Chapman & Hall: London; 1990; 120–34p.

[9]

Gaynor R.D., Meininger R.C., Khan T.S. Effect of temperature and delivery time on concrete proportions. Temperature Effects on Concrete. STP858-ASTM: Phil; 1985; 68–87p

[10]

Nehdi, M., and Al-Martini, S. (2009), “Coupled Effects of High Temperature, Prolonged Mixing Time and Chemical Admixtures on Rheology of Fresh Concrete”, ACI Materials Journal, 106(3), 1-10.

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[11] Al-Martini, S., and Nehdi, M. (2010), “Effects of heat and mixing time on self-compacting concrete”,ICE Construction Materials Journal, 163(3), 175-182.

[12]

Ramachandran V.S., Malhotra V.M., Jolicoeur C., et al. superplasticizers: properties and applications in concrete. Materials Technology Laboratory, CANMET, Natural Resources Canada.

Ottawa: Ontario: 1997; 43–150p.

[13] Al-Martini, S., and Nehdi, M. (2009), “Coupled Effects of Time and High Temperature on Rheological Properties of Cement Pastes Incorporating Various Chemical Admixtures”, Journal of Materials in Civil Engineering, ASCE, 21(8), 1-11, [14]

Al-Martini S., and Al-Khatib, M., (2020) “Rheology of Self Consolidating Concrete (SCC) under Extreme Conditions,” ICE Construction Materials Journal, Theme: SCC, V. 173, No. 5, pp.

215-226,

[15] Al-Martini S., and Al-Khatib, M., (2020) “Self Consolidating Concrete Properties with Binary and Ternary Blends under Hot Weather,” ICE Construction Materials Journal, Theme: SCC, V. 173, No. 5, pp.203-214. (SCOPUS) [16]

Soroka I. Concrete in h BS EN 196-1:2005, 2005. Methods of testing cement - Part 1: Determination of strength, British Standards Institution, London.

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Digital Transformation

Research Bulletin Research Bulletin No.8 September 2023 No.8 September 2023

3D Concrete Printing: A Prospect to Reform Construction?

Haidar Alhaidary Project Executive Middle East Engineering Technologies (MEET) Sharjah, UAE haidar@meetuae.ae

3D concrete printing has the potential to bring much needed reforms into construction such as improving productivity and powering the drive towards smart construction. This short paper examines both the importance and practicality of this ambition by offering a glimpse into the construction of one of the first 3D printed houses in the region. It further outlines one of the major challenges holding back 3D concrete printing from finding its way into mainstream construction.

Keywords: 3D Concrete Printing; Printed House; Construction Project Management; Additive Manufacturing

1. Introduction

3D

concrete printing has been gaining rapid popularity between academics and industry pioneers. However, doubts still remain over its practicality, maturity and profitability. This paper attempts to place 3D concrete printing within the context of buildings construction and shed light on the technology and its application in the construction of one of the first 3D printed buildings in the region – the MEET villa.

Middle East Engineering Technologies (MEET) was formed and operates with the triple helix model of innovation where it seeks to collaborate with and merge the best of what the government, industry, and academia have to offer. The goal is to provide the best benefits and service to its clients and community at large – in line with its vision to leverage innovative technologies that help build future cities with greater economy, comfort, and sustainability.

2. Construction Issues

technologically advanced sectors and put off by the low paid, high risk, and often unconditioned construction environment.

The industry also suffers from infamous project management concerns such as cost and time overruns in addition to high defect rates and rework; with the latter feeding into the industry’s unsustainable image. And to further aggravate the concern with the large amounts of materials consumed (and also wasted), the global construction industry is expected to continue to expand as the demand for cities steadily increases [6,7].

3. 3D Concrete Printing One technology that has the potential to mitigate some of the previously mentioned industry issues is 3D concrete printing. It promises numerous benefits such as less waste, less time, fewer errors, architectural freedom, and an increased attraction to the industry amongst other benefits.

The construction industry suffers from numerous unremitting problems that underscore the need for technological advancements and innovation in the sector.

It has also seen numerous applications with medium to large builds such as concrete wave breakers, furniture, flower pots and fountains, sewer pits, bus stands, company logos as well as buildings and bridges.

The most prominent of which is the issue of productivity. For the past few decades, productivity in the sector has stagnated or even declined worldwide.

A 2017 report by McKinsey and Company [1] illustrated this trend with data from the past 20 years indicating that the productivity growth in construction averaged just 1% per year, compared to 2.8% and 3.6% for the total world economy and manufacturing industry respectively.

3D concrete printing can generally be classified between powder bed printing and extrusion printing, with the latter being the most popular today.

Furthermore, extrusion printing itself can be categorized based on the robot utilized such as gantry printers, robotic arm printers, delta printers, cylindrical or crane-style printers and so on. The first two however are the most popular today and as such, at MEET, we operate a robotic arm printer.

This low productivity negatively contributes to another emerging issue: the shortage of skilled labor. Several reports have progressively called attention to this growing problem [2-5] as the interest in construction by the upcoming generations dwindles. Young workers are increasingly attracted to the more

Our printer consists of an ABB robot mounted on an all-terrain crawler to provide it with on-site mobility, and together with a continuous mortar mixer has been sourced from our technology provider CyBe Construction, Netherlands.

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4. MEET Villa The MEET villa, located at the Sharjah Research Technology and Innovation Park, is an 86.7 m2 two-bedroom house with a living room, kitchen and bathroom. It was designed to have traditional Emirati architecture to create the perfect blend between our culture’s past and the technology of the future.

Fig. 1 The MEET 3D printed villa and company logo.

The house was printed on-site, and in 26 wall segments (including 3 internal partitions) and 19 parapet segments. A sustainable printing material was used and is a specially formulated proprietary mortar that claims a 32% reduction in carbon footprint, sets within three minutes and gains sufficient structural strength in one hour. This allowed the team to print continuously and with printing speeds that reached 500 mm/s, effectively completing all the walls in just over 2 weeks and achieving a productivity gain of about 60%.

The villa depends on a reinforced concrete (RC) structural frame designed to take all the loads on the structure, irrespective of the printed walls’ high compressive strength that reaches 40 MPa. A precast hollow core slab was utilized for the roof to enhance the speed of construction while a raft foundation was utilized to ensure a stable and level platform during printing as well as during the lifetime of the house. It is also pertinent to mention that the 3D printed walls became the formwork for the RC frame, saving on formwork cost and erection time, while also hiding the frame from plain view to add a further level of aesthetics to the design.

Fig. 2 The living room of the MEET villa.

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3D Concrete Printing

One of the key requirements of the house was to ensure it met the insulation requirements of the region and as such the house was insulated from the outside to a target wall U-value of 0.446 W/m2K, with special consideration given to ensure minimum thermal bridging. A thermal scan was conducted to ensure that the thermal bridge design met the requirements, and as shown in Figure 3, the temperature on the exterior surface of the wall had reached almost 60 degrees Celsius while the temperature indoors is at about 16 degrees, with only minimal heat leaks at the intersection of the ground slab and the walls.

Fig. 3 Thermal scan of the villa to detect thermal bridges.

Another major consideration during the design of the house was the MEP (mechanical, electrical, and plumbing) services. One of the advantages of 3D concrete printing is that it forces all MEP design to be completed before the printing commences, effectively ensuring that they are well coordinated and integral with the walls. A portion of the MEP works must be carried out before printing. Another portion can be carried out during printing, however, that would require safety supervision to be heightened and as a result, the team chose to conduct most MEP works after each wall segment has been printed.

Special consideration was also given to frequently serviced MEP elements to provide accessibility during the lifetime of the building as shown in Figure 4.

Fig. 4 Frequently serviced MEP elements were placed in easily accessible locations.

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5. Industry Challenges The importance of the printing material was indicated in the previous section and will be expanded upon here. Some of the benefits of 3D concrete printing such as the quality, level of architectural freedom, and speed are related to the capability of the material.

A printing mortar needs to have the ability to effectively be pumped from the mixer to the nozzle and then upon exiting, take the required shape influenced by the nozzle and have the strength to carry any subsequent layers thereafter.

This ability is the interplay between the material’s characteristics and the printer and printing parameters. In other words, it is printer and product specific.

While printer vendors are often in the best position to develop the best quality and variety of materials for their printers, the overall small market size for 3D concrete printed products and the inherent competition between the printer vendors would prove difficult to capture any economy of scale benefits. As such the high cost of the material would hinder the growth of this nascent industry, and considering it is a direct unit cost, would especially discourage larger projects.

References [1]

F. Barbosa et al., “Reinventing construction: a route to higher productivity,” 2017. Accessed: Feb. 27, 2023. [Online]. Available: https://www.mckinsey.com/~/media/mckinsey/business%20 functions/operations/our%20insights/reinventing%20 construction%20through%20a%20productivity%20revolution/ mgi-reinventing-construction-a-route-to-higher-productivity-fullreport.pdf

[2]

Scape group, “Sustainability in the supply chain,” 2016. Accessed: Feb. 27, 2023. [Online]. Available: https://www.scape.co.uk/ uploads/research/Supply-Chain-Report_Website.pdf

[3]

Turner and Townsend, “International Construction Market Survey,” Apr. 2019. Accessed: Feb. 27, 2023. [Online]. Available: http://www.infrastructure-intelligence.com/sites/default/files/ article_uploads/Turner%20Townsend%20International%20 Construction%20Market%20Survey%202019.pdf

[4]

McKinsey and Company, “The next normal in construction,” Jun. 2020. Accessed: Feb. 27, 2023. [Online]. Available: https:// www.mckinsey.com/~/media/mckinsey/industries/capital%20 projects%20and%20infrastructure/our%20insights/the%20 next%20normal%20in%20construction/executive-summary_thenext-normal-in-construction.pdf

[5]

ABB, “Building the future – How Robotic Automation Can Transform the Construction Industry” 2021. Accessed: Feb. 28, 2023. [Online]. Available: https://library.e.abb.com/ public/86a17cf38a594b8986534b8f83c8e1fa/Construction_ white_paper_v9.pdf?x-sign=mhvG/yKHTfdQ3l5Vepzz2DyCFd2n6/ wAVKBERnZ9SNssitQG7eg5WZAk1iIICvuc

[6]

United Nations Department of Economic and Social Affairs, “World Urbanization Prospects: The 2018 Revision,” New York, 2019.

[7]

M. Betts, G. Robinson, C. Burton, J. Leonard, A. Sharda, and T. Whittington, “Global Construction 2030” Nov. 2015.

Conclusion Overall, 3D concrete printed buildings have shown promising results. The MEET villa, in particular, has undergone numerous summer-winter cycles with no major problems detected, proving that the technology can provide construction benefits with no expected long-term negative effects. The industry, however, does need to collaborate to partially standardize 3D concrete printing to the extent that can make it commercially viable and increase the public’s confidence. Moreover, the success of this technology would benefit the construction industry as a whole as it improves its image, attracts talent, and increases productivity.

Acknowledgements This project would not have been possible without the contribution and support of Ginco Contracting Group – Sharjah, ProArc Architects and Engineers, the Sharjah Research Technology and Innovation Park (SRTIP), CyBe Constructions – Netherlands, and the American University of Sharjah.

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Research Bulletin Research Bulletin No.8 September 2023 No.8 September 2023

The Role of Digital Twin Technology in Optimising HVAC Systems in the Middle East Prof. Hind Zantout Deputy Academic Head and Programme Director MSc Data Science School of Mathematical and Computer Sciences Heriot-Watt University, Dubai Campus Dubai, UAE h.zantout@hw.ac.uk

Omar Al Khairat M.Sc. in Data Science School of Mathematical and Computer Sciences Heriot-Watt University Dubai, United Arab Emirates Oma2000@hw.ac.uk Dr Hassam Chaudhry Associate Professor School of Energy, Geoscience, Infrastructure and Society Heriot-Watt University-Dubai Campus Dubai, UAE H.N.Chaudhry@hw.ac.uk

This article explores the role of Building Management Systems (BMS) and Digital Twin technology in Optimising Heating, Ventilation, and Air Conditioning (HVAC) systems, with a focus on the Middle East. BMS offers numerous benefits in managing energy consumption and ensuring the safety and comfort of the indoor environment. However, the complexity of HVAC systems presents challenges in fault detection and future System degradation prediction.

This can include both the physical deterioration of the system equipment (such as HVAC components wearing out or breaking down) and a decrease in the system’s operational performance (such as reduced efficiency or increased energy consumption). Various maintenance models, including corrective, preventive, predictive, and proactive maintenance, are employed to maintain system reliability and reduce costs. The emergence of Digital Twin technology, a dynamic virtual representation of physical systems, offers a solution to these complexities. This technology allows for real-time tracking and optimisation of HVAC systems, promising improved energy efficiency and sustainability in the Middle East’s buildings.

Keywords: Digital Twin; Heating, Ventilation and Air Conditioning (HVAC); Maintenance; Energy Efficiency; Buildings.

1. Introduction

I

n the rapidly evolving world of technology, the management of Heating, Ventilation, and Air Conditioning (HVAC) systems in buildings has seen significant advancements. One such development is the use of Building Management Systems (BMS) and the concept of Digital Twin technology promises further opportunities and improvements. This article aims to shed light on the importance of these technologies in managing HVAC systems, particularly in the context of the Middle East.

allows for a comprehensive overview of the built environment, including BMS signalling, data flow, and energy delivery from the grid for demand response events.

A high-level overview of the built environment can be seen in Figure 1. The schematic illustrates the primary components of BMSs and their interactions within the broader context of smart buildings. It also highlights the importance of control signals, information flow, and the integration of energy and data supply from the grid for demand response events [1].

2. The Advantage of Building Management Systems Building Management Systems (BMS) offer a multitude of benefits in managing energy consumption. They are instrumental in identifying potential sources of energy wastage and Optimising energy use. By controlling HVAC systems, BMS ensures the safety and comfort of the indoor environment.

Furthermore, they aid in managing other aspects of buildings such as lighting, elevators, and water consumption.

In recent years, efforts have been amplified to control three crucial aspects of buildings: security, comfort, and energy consumption. The integration of BMS

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The Role of Digital Twin Technology in Optimising HVAC Systems in the Middle East

Fig. 1 BMS Signaling Overview [1]

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3. Complexities of HVAC Systems HVAC systems are complex entities comprising several components working in unison to perform specific functions. This complexity extends to detecting, locating, and identifying faults by the embedded sensors and predicting future component degradation. The development of a robust hybrid model for multiple faults becomes increasingly challenging when obtaining faulty data on critical components is difficult.

HVAC system possesses unique characteristics that set it apart from other types of process control. These include nonlinear dynamics, time-varying system dynamics, set-points and disturbances, poor data due to lowresolution analog-to-digital converters (ADCs), and sampling rates. The accuracy of sensors, lack of access to network forecasting and environmental information, interacting and, at times, conflicting control loops, and lack of supervisory control further add to the complexities.

4. HVAC Optimisation

As stated by Kumar [2], there are four HVAC maintenance model types, and they can be classified as corrective (reactive) maintenance, preventive maintenance, predictive maintenance, and proactive maintenance, as shown in Figure 2.

Fig. 2 HVAC maintenance models.

Corrective (Reactive) Maintenance

HVAC optimisation is a comprehensive term that includes various strategies aimed at improving the efficiency and performance of HVAC systems. It involves implementing control algorithms, modifying control schedules and set points, and carrying out minor mechanical adjustments [7].

An optimized HVAC system is characterized by reduced energy consumption due to efficient operation, leading to lower utility costs. Optimisation is not limited to installing the most efficient components or saving energy in one subsystem, but it is a holistic process that considers the entire HVAC system [8, 9].

In the context of high-performance buildings, HVAC optimisation can involve the use of algorithms to find the best combinations of HVAC setpoints based on the current indoor temperature and weather forecast. Without a standard industry definition for HVAC optimisation, it’s crucial to understand that true optimisation should result in tangible energy and cost savings.

HVAC optimisation could be defined as the process of improving the efficiency, performance, and lifespan of HVAC systems through strategic control adjustments, energy-saving measures, and the use of advanced technologies such as digital twins and IoT. This process is aimed at reducing operational costs, enhancing system performance, and extending equipment lifespan, which we would look at through maintenance strategies.

5. HVAC Maintenance Models Maintenance and replacement models play a crucial role in the management of HVAC systems. In the industrial sector, a significant portion of capital is typically allocated towards the production of goods and the provision of services. This often involves the use of complex systems and machinery, which, like all physical assets, are subject to wear and tear over time. This degradation can impact the efficiency and effectiveness of these systems, leading to potential disruptions in production or service delivery. Therefore, proper maintenance of these systems is crucial to ensure their longevity and optimal performance. Various maintenance models and policies have been applied to different forms of systems, with the main goal of achieving low maintenance costs and maintaining system reliability.

Corrective maintenance involves replacing a component of a system when it experiences a fault. This method is inherently uncertain and can lead to severe bottlenecks and interrupted production in extreme conditions.

The inefficiency of this method led to the development of more proactive maintenance models.

Preventive Maintenance Preventive maintenance involves regular maintenance of components and systems to keep them operating and prevent any costly unplanned downtime from unexpected failure. A good practice is to keep records of previous inspections and maintenance actions. It is important to note that the effectiveness of this approach can vary based on the specific characteristics of the assets and their operating conditions. For instance, age, usage, and environmental factors can significantly influence an asset’s degradation rate and, consequently, its maintenance needs. However, a limitation of the preventive maintenance model is that it typically doesn’t account for these variances. It often applies a uniform maintenance schedule to all assets, regardless of their individual conditions or remaining useful life. This lack of customization can lead to inefficiencies, as it doesn’t allow for tailored maintenance measures for each specific case.

Predictive Maintenance Predictive maintenance is the practice of applying maintenance to a component or system before failure to maintain its continuous operation. It leverages the power of Big Data and sensor technology, using past observations and realtime data to build an estimation of a possible asset failure. This approach allows for the prediction of issues before they occur, based on patterns and anomalies detected in the data. For instance, changes in the sound of a compressor, detected and analyzed through sensor technology, can predict an impending failure. Similarly, an increase in the vibration levels of a motor, detected by vibration sensors, could indicate a potential issue with its bearings, allowing for timely intervention. In another example, temperature sensors can monitor the operating temperature of a machine or system. An unexpected rise in temperature could indicate an issue, such as a failing component or inadequate cooling, prompting preventive action. Predictive maintenance can be implemented alongside preventive maintenance,

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providing a comprehensive approach to damage control by continuously monitoring the system and alerting to signs of potential failure.

Proactive Maintenance (Digital Twin)

Hybrid modeling: This model as shown in Figure 4, combines physicsbased and data-driven modelling with big data approaches. It allows for the inclusion of more physics by increasing model complexity. Hybrid models can provide better estimates of related quantities and have been used for tasks such as estimating the mass of solid particles fed into HVAC air filters [5].

In recent decades, new trends have evolved around integrating technologies in the industry and construction world. Industry 4.0, also known as the Industry Internet of Things (IIoT), represents a new phase in the industrial revolution that focuses on interconnectivity, automation, machine learning, and real-time data. It allows for more efficient and flexible processes, enhancing productivity and reducing operational costs. On the other hand, Building Information Modeling (BIM) is a digital representation of the physical and functional characteristics of a facility. It serves as a shared knowledge resource for information about a facility, forming a reliable basis for decisions during its life cycle from inception onward. Both these concepts have been identified as a new generation of modelling that leverages the IoT operations data, providing powerful tools for enhancing asset management and utilizing AI and machine learning for the optimisation of such management systems.

Digital Twin is a digital replica of a living or non-living physical entity. By bridging the physical and the virtual world, data is transmitted seamlessly allowing the virtual entity to exist simultaneously with the physical entity [6].

As depicted in Figure 3, three main approaches for building digital twins were considered: physics-based, data-driven and big data-based hybrid modelling [3].

Fig. 4 Methodology used for building the hybrid model [5].

The concept of Digital Twin emerges as a solution to these complexities.

It provides a dynamic virtual representation of the physical HVAC system, allowing for real-time tracking and optimisation. This technology can outperform traditional techniques, offering a significant advancement over hard techniques, which are based on mathematical models and require a detailed understanding of the system’s dynamics. In contrast to soft techniques, which use computational intelligence methods and offer more flexibility, the Digital Twin approach does not require a detailed mathematical model of the system. However, it does necessitate online updates to enhance model performance and adapt to system changes. Thus, the integration of Digital Twin technology in HVAC systems represents a promising direction for improving maintenance strategies and overall system efficiency.

Digital Twin models have a significant role in enhancing building monitoring systems, particularly in the following areas:

Fig. 3 Building Analytics modeling [3].

Physics-based modelling: This approach uses mathematical representations to understand the behaviour of physical entities. However, it only provides a partial understanding due to the assumptions made, which often ignore significant real physical phenomena.

Data-driven modeling: This method leverages the increasing availability of process data from real-time systems to enhance predictive modelling. Despite its advantages, it can suffer from numerical instability, high computational demands, and model uncertainty.

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Real-time Monitoring and Control: By utilizing Digital Twin technology, HVAC systems can be monitored in real-time, offering crucial insights into system performance and energy usage. This real-time data can be leveraged to promptly adjust control strategies, thereby enhancing system performance and minimizing energy wastage [11].

Integration with Energy Management Systems: Digital Twins can be seamlessly integrated with Energy Management Systems (EMS) to optimize energy consumption. They provide a comprehensive, real-time perspective of energy usage, enabling the identification of inefficiencies and potential areas for energy savings [12].

6. Digital Twin in the Middle East The Middle East is a hub of technological innovation, with numerous mega projects, disruptive exhibitions, research centers, futuristic cities, and innovative universities. The region is making significant moves in digital transformation, with investments projected to surpass $74 billion by 2026.

The Role of Digital Twin Technology in Optimising HVAC Systems in the Middle East

Research Bulletin No.8 September 2023

In recent efforts to utilize the Digital twin research in the middle east, research has been done to emulate the middle east environment [13], the study presents a dataset for the detection of attacks on HVAC systems. The dataset is generated from a real-world HVAC system and includes normal operation data as well as data under various attack scenarios.

The paper discusses the importance of HVAC systems in maintaining a comfortable and healthy indoor environment, and the potential consequences of attacks on these systems, such as discomfort, increased energy consumption, and even health risks.

The dataset includes a variety of features, such as temperature, humidity, CO2 level, and system status, which can be used to detect anomalies and potential attacks. The authors also provide a baseline performance of several machine learning algorithms on the dataset, demonstrating its usefulness for the development and evaluation of HVAC attack detection methods.

Figure 5 presents the building characteristics employed in the study, highlighting the impact of seasonal temperature variations and thermal comfort metrics. This data facilitates an understanding of the relationship between various building units in terms of cooling requirements.

While the study’s data set is robust, it could be further enhanced by incorporating detailed metrics related to occupancy and energy consumption monitoring of the HVAC system. Despite this, the data set serves as a valuable resource for studies aiming to optimize HVAC system performance.

References [1]

Mesa-Jimenez, J. J., Stokes, L., Yang, Q., and Livina, V. N. (2020).

Machine learning for BMS analysis and optimisation. Engineering Research Express, 2(4).

[2]

Kumar, D. and Kumar, D. (2018). Sustainable Management of Coal Preparation. San Diego: Elsevier Science Technology, San Diego.

[3]

Rasheed, A., San, O., and Kvamsdal, T. (2020). Digital twin: Values, challenges and enablers from a modeling perspective.

IEEE access, 8:21980–22012.

[4]

Fortin, C., Rivest, L., Bernard, A., and Bouras, A. (2019). Product Lifecycle Management in the Digital Twin Era 16th IFIP WG 5.1 International Conference, PLM 2019, Moscow, Russia, July 8–12, 2019, Revised Selected Papers / edited by Clement Fortin, Louis Rivest, Alain Bernard, Abdelaziz Bouras. Cham : Springer International Publishing : Imprint: Springer, 1st 2019. edition.

Includes bibliographical references and index.

[5]

Galvez, A., Seneviratne, D., and Galar, D. (2021). Hybrid model development for HVAC system in transportation. Technologies, 9(1):18.

[6]

Grieves, M., & Vickers, J. (2017). Digital Twin: Mitigating Unpredictable, Undesirable Emergent Behavior in Complex Systems. In Transdisciplinary Perspectives on Complex Systems (pp. 85-113). Springer.

[7]

Wassim Ghadban, LinkedIn. (2023). The Future of Digital Twin in Middle East. LinkedIn. Retrieved from https://www.linkedin.com/ pulse/future-digital-twin-middle-east-wassim-ghadban

[8]

ASHOK A KHEDKAR. (2023). HVAC Plant Optimisation, Maintenance and Operations Strategies. Retrieved from https:// ashokakhedkar.com/blog/hvac-plant-optimisation-maintenanceand-operations-strategies/

[9]

arloid. (2023). What is HVAC Optimisation? Retrieved from https:// arloid.com/what-is-hvac-optimisation/

[10]

HVAC Tech Blog. (2023). HVAC System Optimisation for HighPerformance Buildings. Retrieved from https://hvactechblog.com/ hvac/hvac-system-optimisation-buildings/

[11]

Siemens. (2023). Digital Twin for the Built Environment. Retrieved from https://new.siemens.com/global/en/products/buildings/ digital-twin.html

Fig. 5 A sketch of the simulated 12-zone building [13].

The oil and gas industry in the Middle East is leveraging digital tools under the 4th Industrial Revolution (4IR) to enhance speed, efficiency, and safety across the region’s extensive oil field infrastructure. This digital transformation can also significantly help reduce CO2 emissions, reduce waste, preserve water, and more, at the oil fields [7].

Conclusion The adoption of Digital Twin technology in managing HVAC systems in the Middle East has the potential to revolutionize energy consumption and maintenance practices. By leveraging this technology, the region can look forward to improved energy efficiency and sustainability in its buildings.

[12] Schneider Electric. (2023). Digital Twin: The Centerpiece of an Effective Energy Management Strategy. Retrieved from https:// www.se.com/ww/en/work/solutions/for-business/smart-utilities/ digital-twin.jsp [13]

Elnour, M., Meskin, N., Khan, K., and Jain, R. (2021). Hvac system attack detection dataset. Data in brief, 37:107166–107166.

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Adaptive Facades with Zero-Energy Motion Mechanism Using Hygromorphic Thermo-Bimetals Programmable Material Dr. Rana El-Dabaa Assistant Professor of Architecture School of Energy, Geoscience, Infrastructure, and Society Heriot-Watt University Dubai, United Arab Emirates r.el-dabaa@hw.ac.uk

Prof. Sherif Abdelmohsen Professor of Digital Media & Design Computing Department of Architecture American University in Cairo Cairo, Egypt sherifmorad@aucegypt.edu

Adaptive facades are typically used to enhance energy consumption in spaces by programming their motion response to respond to climatic changes. However, the motion mechanisms of these facades require mechanical systems with sensors, actuators, and processors that still consume energy. This article presents the “Hygromorphic Thermo-bimetal Composite” HMTM as a novel programmable material that responds passively with zero-energy consumption to the variation in temperature or humidity and thus can be used as a passive replacement for mechanical motion mechanisms. The significance of this material lies in its ability to program its motion response behavior during its fabrication phase. This article presents the workflow required to program, track, and evaluate HMTM motion response behavior.

Keywords: : Programmable material; Adaptive Architecture; Zero-Energy Consumption motion mechanism; Hygroscopic Properties of Wood, Climate change.

1. Introduction

I

n response to climate change, a growing interest is taking place in adaptive architecture that can self-adjust itself according to environmental conditions [1]. As stated by Moloney, kinetic motion is described by three transformations, translation, rotation, and scaling. Other complex motions as twisting and rolling merge between the three main types of motion, in addition to material distortion that relies on material properties [2]. Traditionally, adaptive structures rely on mechanical systems that are programmed to sense, process, and actuate according to the external stimulus to reduce energy consumption used in lighting, cooling, and heating buildings, however, this motion mechanism still requires energy to perform. Getting inspired by nature specifically how some plants are responding to climatic change by bending and folding mechanisms instead of mechanical [3].

“End of Mechanism” is a paradigm shift that has been argued by Fox and Kemp to replace mechanical kinetic systems with passive soft biological systems [4]. While Mark Weiser’s stated, “The most profound technologies are those that disappear. They weave themselves into the fabric of everyday life until they are indistinguishable from it” [5]. In parallel, the smart materials interface is developing and promising the ability to weave into everyday life as a response to the essence of ubiquitous computing [5]. From this perspective, recommendation of smart materials is recommended due to their ability to be utilized to passively mimic biological systems by controlling their motion response and programming the material properties [6].

This article is exploiting the latent properties of Hygromorphic Thermobimetals composite material during the fabrication phase, which can passively respond to the fluctuation of temperature or humidity with continuous and reversible motion response. HMTM material is being utilized as a low-cost and low-tech adaptive facade system with zero energy consumption.

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This article presents HMTM as an approach for low-cost and zero-energy adaptive facades, through controlling its latent properties to regulate and program its passive continuous and reversible motion response mechanism to external stimuli. The significance of HMTM lies in its ability to perform in different climatic zones as it is triggered by the two main aspects of climate configuration: temperature and humidity variation.

2. Hygromorphic Thermo-Bimetals (HMTM) Smart materials are mainly characterized by their ability to change in size and form with reversible and bi-directionality behavior when exposed to external stimuli [6], [7]. This article presents “Hygromorphic Thermo-Bimetals” HMTM as a new programmable material, that can be programmed during the fabrication process to self-regulate its form in response to temperature or humidity variation. This motion response is considered a significant addition to the field as it requires zero-energy consumption to alter its properties.

HMTM is a composite material that merges between the hygroscopic behavior of wood and the difference in metal’s expansion coefficients as in the bimetal.

It consists of a minimum of two laminated layers of wood and metal. HMTM shows an infinite number of possibilities in terms of which type of wood and metal to be laminated together. However, the focus of this article is on beech veneer and aluminum. Tropical deforestation counts as human-caused 20% of carbon dioxide emissions. Carbon is stored in wood and is released when a tree dies, however, if the tree is utilized to produce wooden products, it still maintains the carbon [8]. The selection of wood is due to its low embodied energy, and carbon impact in addition to its ability to change its volume when exposed to humidity [8].

Adaptive Facades with Zero-Energy Motion Mechanism Using Hygromorphic Thermo-Bimetals Programmable Material

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3. Utilizing Embedded Material Intelligence in Adaptive Architectural Facades Utilizing embedded material intelligence in the adaptive architecture realm requires experimentation and validation phases. Development of Hygromorphic Thermo-bimetals requires five years of research for the validation and experimentation with different environmental configurations.

This article presents the research workflow used to develop HMTM as shown in Fig 1.

3.1 Physical Interface The workflow begins with a physical interface that encompasses experimenting with several metals and wood behavior when exposed to variations in temperature and humidity respectively, in addition to comparing the experiment results to the shrinkage and expansion coefficient of the materials [8]. The physical phase consists of two parts: fabrication and experimental phases.

Fabrication Phase Experiments took place to define the embedded and controlled parameters of HMTM and its impact on the response behavior of the sample. A set of parameters was deduced and defined as the motion indicators that can be controlled to program the desired motion response of HMTM. The fabrication phase took place using two techniques, using natural wood veneer as; Beech and Spruce and metal sheets as; Aluminum and Copper. The combination of these elements shows different motion responses with different angles of curvature and speed responses. The fastest speed response was HMTM with Beech and Aluminum while the slowest was Spruce and Copper. This is due to the shrinking value of Beech being higher than Spruce and the expansion coefficient of Aluminum being higher than Copper. Several material configurations were tested to be able to trace the effect of a material change in each layer. Also, several lamination techniques were tested, finding that Silicone based lamination can handle humidity and heat in addition to maintaining the flexibility of the material. Another fabrication technique for HMTM is the 4D printed version of the material. This option allows for better control of the wood fibers and avoids the natural variations in each sample.

However, due to the percentage of PLA added to the wooden filaments, this reduced the angle of curvature and speed response in comparison to the natural materials [9].

Physical Experiments

Fig. 1 Workflow of the research showing its phase from fabrication, experimentation and simulation to validation and its use in adaptive architectural facades

Experiments took place in a sealed-controlled humidity and temperature chamber. Readings are recorded every 30 seconds for the angle of curvature for three identical samples and the average is calculated for each material used. The outcome of these experiments reveals the HMTM embedded and controlled parameters. The embedded parameters include the type of wood vs metal required for architectural facades, the percentage of each material, lamination technique, dimensional aspect ratio, thickness of each material, grain orientation of the wooden layer, and its moisture content during the fabrication phase. While the controlled parameters are fixation position and type of the samples on the façade, percentage and location of isolated areas within the samples, and the lamination configuration. Research first began using natural materials then moved to 4D printing of the HMTM for mass customization and more control of the materials. This change resulted in revealing new parameters related to the printing properties such as infill height, pattern, and percentage of natural wooden particles vs Polylactic acid in filaments. The experiments took place with variation of humidity levels from 50% to 90% and temperature from 15 ºc to 40 ºc. Humidity and temperature sensors are kept monitored during the experiments, in addition to a professional camera supported at a fixed distance from the chamber to record the HMTM shape-shifting phases. Three markers are added on the sample’s side to facilitate the tracking process in the digital phase. The output of the physical interface phase is the HMTM shape-shifting configuration as a response to the temperature and humidity variation, and the effect of each HMTM design configuration on controlling its angle of curvature and speed response [10].

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3.2 Digital Interface The role of the digital interface of the research workflow lies in the simulation and validation of the HMTM passive motion response. The digital interface is divided into two parts: image analysis and digital simulations. Kenova; a validated Image-analysis software for motion tracking [11] is used to measure and track the change in HMTM angle of curvature when exposed to variation in temperature or humidity [12].

References [1]

A. Menges, Material synthesis: fusing the physical and the computational, vol. 85. in Architectural Design Profile, no. 237, vol. 85. London: Wiley, 2015.

[2]

J. Moloney, Designing kinetics for architectural facades: state change. Abingdon, Oxon ; New York: Routledge, 2011.

The second part of the digital interface is the environmental simulations using Grasshopper graphical algorithm editor to develop a closed parametric loop between the input parameters of HMTM material design parameters, output motion response as different adaptive design scenarios, and its environmental effect on the building’s energy consumption, daylight analysis, and how its motion response behavior has different percentages of shading configurations.

[3]

S. Schleicher, J. Lienhard, S. Poppinga, T. Speck, and J. Knippers, “A methodology for transferring principles of plant movements to elastic systems in architecture,” Comput.-Aided Des., vol. 60, pp.

105–117, Mar. 2015, doi: 10.1016/j.cad.2014.01.005.

[4]

M. Fox, Ed., Interactive architecture: adaptive world, First edition. in Architecture briefs. New York: Princeton Architectural Press, 2016.

Discussion and Conclusion

[5]

A. Nijholt and A. Minuto, “Smart material interfaces: Playful and artistic applications,” in Conference on Imaging, Vision & Pattern Recognition (icIVPR), Dhaka, Bangladesh: IEEE, 2017, pp. 1–6. doi: 10.1109/ICIVPR.2017.7890882.

[6]

M. Kretzer, Information materials: smart materials for adaptive architecture. Switzerland: Springer International Publishing, 2017.

[7]

D. M. Addington and D. L. Schodek, Smart materials and new technologies: for the architecture and design professions.

Amsterdam ; Boston: Architectural Press, 2005.

[8]

A. Ritter, Smart materials in architecture, interior architecture and design. Basel ; Boston: Birkhäuser, 2007.

[9]

Forest Products Laboratory, Wood handbook: wood as an engineering material. Madison, Wis.: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory., 2010.

Testing the implementation of hygroscopic properties of wood in adaptive facades took place in three international workshops at Princeton University, Rome Tre University, and American University in Cairo for undergraduate and postgraduate students. Students were required to go through the physical interface and fabricate adaptive facades using the hygroscopic behavior of wood. The outcome of the workshops showed two options for utilizing the embedded material intelligence in adaptive architectural facade design, either using this property to design adaptive hinges or adaptive panels as shown in Fig 2 [13].

Fig. 2 Implementing hygroscopic behavior of wood in adaptive architecture facades [13].

HMTM material is still under development and requires several studies related to durability and stress studies. While the limitation of the study lies in the shortage of filaments that have 100% wooden particles and metal particles with the percentage of PLA added to the filament.

Acknowledgements The authors are grateful for the funding provided by the Bartlett’s Fund for Science and Engineering Research Collaboration, the support of the American University in Cairo, Princeton University, and University Roma Tre, and the efforts of Professor Sigrid Adriaenssens, Stefano Gabriele, and Luciano Teresi in initiating and pursuing this field of research since 2017.

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[10]

R. El-Dabaa, I. Salem, and S. Abdelmohsen, “DIGITALLY ENCODED WOOD: 4D Printing of Hygroscopic Actuators for Architectural Responsive Skins,” presented at the ASCAAD 2021 - Architecture in the Age of Disruptive Technologies, American University in Cairo, Egypt, 2021.

[11]

S. Abdelmohsen, P. Massoud, R. El-Dabaa, A. Ibrahim, and T. Mokbel, “The Effect of Hygroscopic Design Parameters on the Programmability of Laminated Wood Composites for Adaptive Façades,” in Computer-Aided Architectural Design. “Hello, Culture,” J.-H. Lee, Ed., Singapore: Springer Singapore, 2019, pp.

372–383. doi: 10.1007/978-981-13-8410-3_26.

[12] A. Puig-Diví, J. M. Padullés-Riu, A. Busquets-Faciaben, X. Padullés-Chando, C. Escalona-Marfil, and D. Marcos-Ruiz, “Validity and Reliability of the Kinovea Program in Obtaining Angular and Distance Dimensions,” Preprints, vol. 1, 2017, doi: 10.20944/preprints201710.0042.v1.

[13]

S. Abdelmohsen, P. Massoud, R. El-Dabaa, A. Ibrahim, and T. Mokbel, “A Computational Method for Tracking the Hygroscopic Motion of Wood to develop Adaptive Architectural Skins,” in eCAADe 2018: 6th Annual Conference on Education and Research in Computer Aided Architectural Design in Europe, Lodz, Poland, 2018, pp. 1–9.

[14] S. Abdelmohsen, S. Adriaenssens, S. Gabriele, L. Olivieri, and R. El-Dabaa, “Hygroscapes: Innovative Shape Shifting Façades,” in Digital Wood Design : Innovative Techniques of Representation in Architectural Design., F. Bianconi and M. Filippucci, Eds., in Lecture Notes in Civil Engineering, vol. 24. Switzerland: Springer, 2019, pp. 675–702. doi: 10.1007/978-3-030-03676-8_26.

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Research Bulletin Research Bulletin No.8 September 2023 No.8 September 2023

Lean Leadership for Delivery Excellence Dr Ramez Alchamaa Senior Lean Construction Specialist Road & Infrastructure Dept.

Dorsch Gruppe Doha, Qatar ramez.alchamaa@dorsch.com

Zied Dahmani Senior Engineer - Lean Management Transportation Business Line AECOM Doha, Qatar zied.dahmani@aecom.com

Decision-making is part of the daily duties of researchers, engineers, and consultants, and taking the right decisions is an essential competence in today’s complex networks. This case study is a testimonial of the benefits of adopting a lean construction philosophy that drives collaboration, best practices standardization and continuous improvement. The case study describes how simple daily practice can lead to better reliability and predictability of activities on the project, considering all associated constraints and risks. The paper highlights the lean practice evolution into a lean leadership model that empowers project teams and establishes a harmonious working environment based on psychological safety to successfully deliver projects to the client’s expectations.

Keywords: : Lean Construction (LC); Collaborative Pull Planning Sessions; Daily Huddles; Project Performance Centre; Continuous improvement.

1. Introduction

M

odern construction projects face frequent burdens related to shorter durations and uncertainty throughout their life cycle (Koskela et al., 2002) [1]. The crucial challenge in these current projects lies in the activities and tasks miscoordination among the project’s different teams as the traditional approach for projects delivery is typically utilized. Given that the implementation of the Lean Construction (LC) principles and tools becomes a recognized approach worldwide to help reduce the activities scheduled uncertainty in the preliminary plan (initial) schedule at high-level details. Then, going ahead with such activities execution without properly eliminating the associated constraints might lead to an unreliable workflow that can hinder the overall project progress. Adopting the LC advanced approach in project management has become a strategic intent to enhance collaboration and communication with stakeholders and residents and reinforce workplace safety and organization. As a result, this would speed up the project’s delivery time and improve overcoming challenges the project may face promptly by recognizing and prioritizing them early.

Likewise, by implementing the LC principles appropriately, each construction phase is planned for and controlled closely, regularly holding Collaborative Planning Sessions in the Project Performance Centre (i.e., The Big Room) involving all stakeholders. Using various facilitation approaches to encourage consensus and cooperation is an efficient tool to streamline a project’s performance in all aspects.

2. Background about Last Planner System® (LPS), Collaborative Pull Planning, and Daily Huddles

Herman Glenn Ballard developed the Last Planner System®, and it is broadly described in H. G. Ballard (2000) [2]. It is grounded on the idea that reliable planning cannot be done much before planning activities in dynamic environments with high uncertainty and variability. The Last Planner production control system is found in the industry under various names and with different levels of implementation. The method comprises four fundamental concepts about the assignments to be completed: should, can, will, and did. Assuming the higher levels of planning (i.e., Master Plan) are specified, detailed planning contains what should be done next. Unfortunately, it is not always possible to perform those activities due to several obstacles.

Hence is essential to look further at what should be done and be sure that it can be done before bringing it to the immediate plan. The planning process then should match what “should” be done within the constraints of what “can” be done so that the activities “will” be performed. Ensuring that the activity or task is completed and the constraints for the next activity are removed will be part of what the project “did”.

Also, Collaborative Pull Planning aims to produce a plan that maximizes value generation. This is to deliver projects more safely; create a more predictable production program; reduce project durations; better manage costs; reduce stress on project management staff; improve the overall production process; this system works in a way that traditional Critical Path Methods (CPM) does not.

The traditional way of thinking and planning in project management is based on establishing the longest sequence of activities path that should be followed without examining the constraints, floats, risks associated with it.

Traditional planning system (Push Planning) is presented in Fig. 1. A Pull System of the Last Planner System® is presented in Fig. 2.

Referring to the McKinsey Global Institute report in 2017, it is worth noting that 70% of construction projects in the world fail to complete on budget, and 61% of them with delays in the schedule.

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the weekly work plan, which identifies activities free of constraints made ready through the lookahead process assessing near-term work identified during the phase pull planning process that supports the workflow of planned activities to meet target dates established during master planning. The huddle allows problems to surface early and daily adjustments to be made in response to changing and unexpected conditions. These quick adjustments enable the project to remain on plan without significant replanning.

Daily huddles need to be short: they last 15-20 minutes. During construction, they can be held close to the work in the field. A typical agenda covers these topics from each Last Planner® or their representative.

Fig. 1 The Traditional (Push Planning) System (reproduced after H. G. Ballard 2000).

Here are some recommendations when planning and holding daily huddles to make them more effective.

The huddle should be brief; if an issue requires extended discussion, it can be discussed afterward.

The completion of the work listed on the weekly work plan during the huddle should be recorded in addition to what happened kept activities from being completed as planned.

There should be no partial credit or credit for almost completing work.

Activities are either 100% complete as planned or not.

Fig. 2 The Last Planner (Pull Planning) System (reproduced after H. G. Ballard 2000)

More than one huddle should be considered in large projects with people working in different locations; Huddles include people whose work is interdependent daily and weekly.

This paper emphasizes the importance of using practical lean construction tools (i.e., Last Planner System®, daily huddles, and end-of-shift debriefs), among others, during the construction phase of any project for a more reliable and predictable workflow of the planned activities that provide vital support to have a better consistent schedule that can be monitored and controlled expediently. As a result, cost overruns can be optimised if not eliminated in most cases once the accumulated operational wastes are identified, investigated and prevented during the project’s lifetime.

Each participant needs to be prepared to discuss their work commitments without encouragement from the leader of the huddle.

It is also interesting to highlight the importance of having a Visual Performance Center (VPC) in a project or “The Big Room”, which is a space where the project’s different teams can meet to create a plan to deliver the project with the Last Planner System®. However, the purpose of the VPC goes well beyond that of being a meeting place. It is a place where teams are formed and empowered to practice collaborative decision-making. It is also a place to make commitments and build trust through the delivery of promises by project teams. The VPC environment fosters behaviors that lead to high levels of collaboration, where the project’s goals become dominant to the teams involved. The VPC is where the lean culture and its principles are encouraged to allow the project teams to create maximum value for clients.

Moreover, the daily huddle is defined as a stand-up meeting each day by groups of interdependent players, at which each, in turn, shares what commitments they have completed and what commitments they need help with or cannot deliver. The huddles can be held within a design or construction team and between front-line supervisors of design teams or construction teams.

This process would improve the relationships across a team as problems begin to be addressed directly and swiftly on the spot rather than run through a chain of command. The Last Planners (construction teams) start to work as one team rather than a group of disconnected players.

For the designated project in this paper, the authors present the importance of the following: 1. A visual project performance center (i.e., The Big Room) for communicating and sharing daily updates, progress, and issues.

2. Conduct regular collaborative planning sessions involving all project team members.

3. Empower the project teams and enhance transparency and accountability as a compulsory standard for every team member.

3. Overcoming Challenges and Emergent Barriers on an Infrastructure Project

The daily huddle is an essential element of the Last Planner System®, meaning that if a project is not holding daily huddles, it is not practicing the Last Planner System®. The commitments reviewed in the huddle come from Lean Leadership for Delivery Excellence

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The case study in this paper is for a designated road and infrastructure project, namely Project A. The chronological chart in Fig 3 illustrates the project’s performance from the project’s starting date in July 2019 till the end of December 2021. A couple of months later, following the start date, particularly in October 2019, the project started suffering from a gradual increment of the reported percentage of negative variance (delays) as per the original baseline schedule. The peak point of the reported delays (i.e., a cumulative variance of -37%) occurred in June 2020 due to different events including, but not limited to, COVID-19, where the project has been forced to adapt signiffcant challenges and formulate tailored solutions to mitigate the delays and other impacts caused by COVID-19.

This shift is attributed to the effective collaborative pull planning, the focus on productivity improvement by eliminating operational waste and other lean implementation activities (i.e., daily huddles) with the broad participation of different teams from both the Supervision Consultant and the Contractor associated with an operative implementation of the agreed enhancement and lean strategy for the project as of May 2021.

In July 2020, the Project’s Leadership, from the Supervision Consultant and the Contractor, built an effective collaborative environment for the project.

Firstly, the formed collaborative environment has targeted overall cultural change and the spread of the cooperative mindset among team members in the project. The established environment has encouraged the interactive transfer of knowledge in a structured way inside the organization, in which all voices are heard, and all contributions are valued within a safe and open dialogue space focused on asking questions and providing inputs on various subjects and issues.

It is vital to highlight the valuable impact of systematic learning and knowledge transfer in Project A. Leadership role model in facilitating and driving the lean practice and evolution into a project teamwork culture is based on the efficient exercise of the PDCA cycle for continuous improvement. Key success factors are identified as follows:

4. Lean Leadership model for successful project delivery

1. Strong Team Communication: Ensure daily huddles are attended by all project teams and led by PM for 15-20 min as a recap of: what is achieved? Any missed targets? Why was it missing? How to mitigate?

What is the target for tomorrow? Is it achievable? Any support needed?

Besides, Visualization using proper charts and layout in a big room or visual performance center is essential for an effective daily huddle.

2. Empowering the team: Delegation of decision-making at the operational level with an acceptable tolerance; setting clear and measurable commitments; establishing an accountability culture through engagement in planning and execution (Tillmann et al. 2012).

Also, create a psychologically safe working environment where project members speak freely without concerns about being punished or humiliated. It is the foundation for the team to trust each other and set up a mindset of reliability in making and keeping promises.

Fig. 3 Major Events in Project A’s Performance.

Furthermore, a recovery plan to minimize the excessive delays was prepared collaboratively between different teams from the Supervision consultant and the Contractor in July 2020. It resulted in the production and implementation of a new revision of the Activity Program as a practical tool for monitoring the performance against planned activities with actual daily rates. It also allocated resources for each planned activity to ensure a predictable and reliable workflow of on-site construction activities. Remarkably, the weekly performance of the project started to improve dramatically, with a considerable decrement in delays in the schedule as of August 2020 onwards.

The delays began to decrease to an acceptable magnitude of ≤5% in February 2021 following the active implementation of the lean construction philosophy and its practical tools in the project with the operative engagement of the Leadership and teams from different disciplines.

It is worth mentioning that the recorded delay in schedule has decreased signiffcantly to the magnitude of ≤1% as of June 2021 and maintained to be around this percentage till the end of 2021, as demonstrated in Fig. 3.

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3. Continuous Improvement: Challenging the status quo: it is an attitude that needs space and time to be harnessed. Then, adopting standard lean construction practices such as GEMBA walks, 5S, etc, to collect, analyse and assess data for the purpose of findings what can be improved? Then how?

Last, Lean Leadership is a new and powerful approach to steer a project toward success in a disruptive ecosystem.

Conclusion This paper offers an inside view of a successful lean journey for a designated infrastructure project in the State of Qatar, including a description of the project status and emergent impediments at the initial stage of a selected project under the Enhanced Contracts framework. The presented study in this paper displays the importance of lean leadership to ensure a successful transformation in the Construction industry and the development of a competent excellence delivery model for Construction projects. The leadership and teams’ non-adoption of the lean culture is influenced by barriers mostly related to people, organizational processes, and other operational aspects. The analysis of these barriers was used to form a solid base for the operative preparation and deployment of

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customized LC activities, remarking that addressing the organizational culture factors in Construction was necessary to successfully implement practices (Cheung, Wong, & Wu, 2011) [3].

References [1]

Koskela, L. and Howell, G., (2002). The theory of project management: Explanation to novel methods, In Proc. 17th Ann. Conf. of the Int’l Group for Lean Construction, Gramado, Brazil, August 6-10.

[2]

H. G. Ballard, The last planner system® of production control (Doctoral dissertation, The University of Birmingham 2000).

[3]

Lastly, It is value mentioning that Project A has focused on delivering value for the Client that supports building a relationship of trust with the Client; the project had a reasonable overall percentage of approved Extension of Time (EoT) that reflects the consistency in Project A’s performance.

Cheung, S. O., Wong, P. S. P., & Wu, A. W. Y. (2011). Towards an organizational culture framework in Construction. International Journal of Project Management, 29(1), 33-44. DOI: http://dx.doi. org/10.1016/j.ijproman.2010.01.014

[4]

Kumar S, Deshmukh V, Adhish VS. (2014) Building and leading teams. Indian J Community Med.;39(4):208-13. DOI: 10.4103/0970-0218.143020. PMID: 25364143; PMCID: PMC4215500

Acknowledgements

[5]

Tillmann, P. , Tzortzopolous, P. , Sapountzis, S. , Formoso, C. & Kagioglou, M. (2012), ‘A Case Study on Benefits Realisation and Its Contributions for Achieving Project Outcomes’ In:, Tommelein, I. D. & Pasquire, C. L., 20th Annual Conference of the International Group for Lean Construction. San Diego, California, USA, 18-20 Jul 2012

Furthermore, the records of Project A reflect the flexibility generated through leadership engagement and project members’ empowerment.

Establishing the lean activities routine manifested the development of the “Tuckman Ladder Model” five stages within the project (Kumar et al.

2014) [4]. Project A success in progress recovery and on-time delivery resulted in receiving client appreciation.

Authors appreciate PWA-RPD for the opportunity to practice lean construction concepts and elevate the best practices capabilities.

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Community Development

Research Research Bulletin Bulletin No.8 2023 No.2September December 2020 No.8 September 2023

The Role of Advanced Machine Learning in Construction Site Safety Fatemeh Mostofi Ph.D. student Civil Engineering Department Karadeniz Technical University Trabzon, Türkiye 393989@ogr.ktu.edu.tr

Prof. Vedat Toğan Civil Engineering Department Karadeniz Technical University Trabzon, Türkiye togan@ktu.edu.tr

Dr Onur Behzat Tokdemir Associate Professor Civil Engineering Department Istanbul Technical University Istanbul, Türkiye otokdemir@itu.edu.tr

The potential of machine learning (ML) approaches for reducing site accidents has already been established. However, the effectiveness of ML construction safety prediction models is often hindered by issues related to the quality, reliability, and abundance of input data. Generative Adversarial Networks (GANs) and autoencoders through data augmentation and anomaly detection can enhance the reliability of construction safety prediction models, offering the promising potential for data-related challenges of existing ML-based site safety solutions. Correspondingly, this article highlights the potential of advanced ML methods, particularly GANs, and autoencoders, in accelerating actions toward achieving excellence in construction safety management. Utilizing these advanced ML approaches demands collaborative efforts from researchers, construction professionals, and policymakers. First, construction professionals must invest in data preparation. Policymakers must create a supportive regulatory environment that encourages the adoption of advanced ML techniques. Finally, there is a need for more focused research studies on applying these ML approaches to construction site safety.

Keywords: Site safety management, Generative Adversarial Networks (GAN), autoencoder, data augmentation, anomaly detection, machine learning.

1. Introduction

D

ue to their true uncertainty and dynamism, construction sites are constantly posed with a fresh set of challenges and safety scenarios. Over the years, Machine Learning (ML) approaches have been employed to enhance safety measures, providing a wide range of solutions such as predicting the severity outcome of construction accidents [1], falling from height [2], and hazard recommendations [3].

Various ML approaches, such as shallow learning [1], deep learning [4,5], ensemble [6,7], and graph-based [8] ML models, have contributed to a reduction in accidents and overall safety improvement. These ML approaches have primarily focused on the prediction accuracy of construction safety prediction models. Although these models have shown promising results in terms of accuracy, they often fail to address other challenges associated with construction safety management.

A key challenge in deploying ML-based solutions is the availability of highquality labelled data, which ensures its accuracy and reliability. Considering the dynamic and complex environments of construction sites, capturing

the diversity of these environments in a dataset can be challenging. It is time-consuming and requires specialized knowledge. An abundance of construction safety datasets can directly affect the predictive performance of the ML model. In addition, higher-severity accidents are less frequent than medium- and low-severity accidents, which often cause an imbalanced training dataset. In this respect, advanced ML approaches, particularly Generative Adversarial Networks (GANs) and autoencoders, with their ability to generate new data that mirror the input data, can create realistic construction site scenarios for safety training and prepare workers for a wide variety of situations. Another challenge is mistakes and errors during data collection and recording procedures. Construction safety incidents are often underreported or misreported, leading to mislabeled data. This can significantly affect the performance of ML models because they rely on accurate labels for training.

Traditional ML models often struggle with issues related to the quality, reliability, and abundance of the input data. Figure 2 shows the potential application of the GANs and autoencoders for improving the quality of the input in ML-based construction safety solutions.

The Role of Advanced Machine Learning in Construction Site Safety

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Advanced ML approaches, GANs, and autoencoders have the potential to enhance the quality of construction safety prediction models in the absence of an adequate input dataset. These advanced ML approaches have been extensively studied and applied in various domains [9–11], demonstrating their superior capabilities in handling complex and diverse data. Addressing the issues of data quality, abundance, and mislabeling is expected to enhance the performance of the construction safety prediction models. Therefore, this article delves into the potential of these advanced ML techniques for enhancing site safety management.

Fig. 2 Deployment of GAN for improving site safety prediction model.

Research on GANs in other fields has demonstrated their potential for generating high-quality realistic images [11]. This allows the GAN to augment realistic construction site scenarios, thereby increasing the number of scenarios that the ML-based predictors learn. This, in turn, enhances the comprehensiveness of the construction safety prediction model without costly and time-intensive data collection and recording procedures.

Fig. 1 Potential applications of the advanced ML approaches in improving the quality of the ML-based site safety solutions.

2. Generative Adversarial Networks (GANs) GANs [12] are powerful ML approaches that can grow existing data and mirror input data characteristics. They used a two-part system of a generator and discriminator, whereby the generator creates new data instances, and the discriminator evaluates the authenticity of these instances. Thus, the GAN learns to generate new synthetic images or augment imbalanced datasets through a continuous feedback loop between the generator and the discriminator. Figure 2 outlines the potential application of the GAN for generating synthetic constructions after the dataset.

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The augmentation of existing accident data can be beneficial when dealing with imbalanced, missing, or small-sized site safety records, thereby helping improve the performance of safety prediction models. GAN’s ability to create a balanced and diverse dataset for training ML models can be particularly useful in scenarios where certain types of accidents are underrepresented in the data because of their low occurrence rate. GANs can generate synthetic data for these underrepresented scenarios, thereby ensuring that the ML model is well-trained to handle such situations. This can significantly enhance the performance of these models because they can learn from a wider variety of scenarios.

This can also be useful in scenarios where certain safety incidents are underrepresented in the data. The application of GANs in construction safety is still in its early stages, and further research is needed to realize their potential fully. Specifically, GANs can be used to generate synthetic images of construction sites, which can then be used to train ML models. For instance, GANs can generate images of various safety incidents, which can help in training ML models to recognize such incidents.

In addition, GAN was recently employed for limited medical images, whereby adding synthetic images to the original training dataset improved the prediction performance by up to 7% [13]. Accordingly, it is expected that the augmentation of more diverse accident scenarios allows the creation of a balanced and diverse dataset for training the ML models, which in turn improves the prediction accuracy of the ML-based prediction model. It should be noted that the potential applications of GAN for improving safety status at construction sites are not limited to improving the quality and reliability of

Research Bulletin No.8 September 2023

the input dataset. For example, GANs can be used to simulate various safety scenarios, which can be used for safety training. Workers can be trained in these simulated scenarios to prepare them for a wide variety of situations.

3. Autoencoders A crucial aspect of ML solutions is the quality and trustworthiness of the input dataset. Any error, mistake, or bias during data collection and recording can blur the prediction of the ML-based solution. To this end, autoencoders can also be trained to identify normal patterns, which makes them good detectors for flagging deviations from the norm as anomalies. In the context of construction safety management, an autoencoder can be trained to recognize normal operation patterns at a construction site, and any deviation from this pattern can be flagged as a potential safety hazard. The anomaly detection potential of autoencoders allows them to monitor and control manually or auto-collected data from various sensors at a construction site, thereby detecting any abnormal readings. This ability to detect anomalies can also be beneficial for identifying mislabeled data. For example, if a certain data point is labeled as “safe,” but the autoencoder identifies it as an anomaly, it could indicate that the data point has been mislabeled. Such insights can help improve the data quality used for training the ML models, thereby enhancing their performance.

Like GAN, the autoencoder can also augment data by learning to encode the input data into a lower-dimensional space, then decode this representation back into the original space. Autoencoders can be used to reduce the noise in data, thereby enhancing the quality of the data. It is not always possible to train ML models on a clean dataset without noise or large outliers [10].

As a result, the noise reduction ability of autoencoders can be specifically advantageous for construction safety prediction models, considering that construction site data are often noisy owing to various factors, such as sensor errors and manual recording errors.

Another potential application of autoencoders is learning to reconstruct an input dataset and generate a new training dataset. Data augmentation can be used to increase the number of training datasets or improve the number of underrepresented accident classes. For instance, variational autoencoder (VAE) improved the prediction accuracy of the ML model by up to 8% by utilizing imbalanced road accident data (625 crashes and over 6.5 million crash and non-crash records) [9].

It is worth mentioning that potential applications of autoencoders are not limited to anomaly detection and augmentation of construction safety datasets. Other applications, such as feature extraction from the input dataset, can improve the prediction accuracy of the ML model. For example, autoencoders can extract important features from high-dimensional data, such as image data from CCTV footage, thereby improving the computational efficiency of ML models.

of the input data when used for data generation. However, autoencoders, less data-intensive than GANs, require significant data for effective noise reduction and feature extraction. Another challenge is the complexity of the models. GANs and autoencoders are complex models requiring specialized skills and computational resources for implementation and training. This can be a barrier to their adoption in the construction industry, which is often characterized by resource constraints.

In conclusion, one of the main challenges of ML-based construction management solutions is the need for large amounts of high-quality labeled data to train these models. Although GANs and autoencoders offer promising solutions to the challenges of data scarcity, imbalance, and quality in construction safety management, their adoption in the industry is not without challenges. Overcoming these challenges will require a concerted effort from researchers, construction professionals, and policymakers. Future research should focus on developing more efficient and user-friendly implementations of these models and strategies for overcoming data requirements.

References [1]

V. Togan, F. Mostofi, Y. Ayözen, O. Behzat Tokdemir, Customized AutoML: An Automated Machine Learning System for Predicting Severity of Construction Accidents, Buildings. 12 (2022) 1933. https://doi.org/10.3390/buildings12111933.

[2]

Y. Piao, W. Xu, T.-K. Wang, J.-H. Chen, Dynamic Fall Risk Assessment Framework for Construction Workers Based on Dynamic Bayesian Network and Computer Vision, J Constr Eng Manag. 147 (2021). https://doi.org/10.1061/(asce)co.19437862.0002200.

[3]

F. Mostofi, V. Togan, Construction Safety Hazard Recommendation using Graph Representation Learning, in: 7th International Project and Construction Management Conference (IPCMC 2022), PCMC 2022, Istanbul, 2022: pp. 1376–1386. https://www.researchgate. net/publication/365235944_Construction_Safety_Hazard_ Recommendation_using_Graph_Representation_Learning (accessed December 9, 2022).

[4]

F. Mostofi, V. Togan, H.B. Basaga, Real-estate price prediction with deep neural network and principal component analysis, Organization, Technology and Management in Construction: An International Journal. 14 (2022) 2741–2759. https://doi. org/10.2478/otmcj-2022-0016.

[5]

F. Mostofi, V. Togan, H.B. Basaga, House price prediction: A datacentric aspect approach on performance of combined principal component analysis with deep neural network model, Journal of Construction Engineering, Management & Innovation. 4 (2021) 106–116. https://doi.org/10.31462/jcemi.2021.02106116.

[6]

F. Mostofi, V. Togan, Y. Ayözen, O. Behzat Tokdemir, Predicting the Impact of Construction Rework Cost Using an Ensemble Classifier, Sustainability. 14 (2022) 14800. https://doi.org/10.3390/ su142214800.

Discussion and Conclusion Despite their potential, applying GANs and autoencoders in construction safety management requires overcoming several issues. The amount of data required for effective data augmentation can be substantial, particularly for GANs. Compared with GAN, autoencoders can augment datasets with fewer input datasets; however, they tend to reconstruct datasets closer to the average of the input data. Therefore, GANs may better capture the full diversity

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[7]

A. Mammadov, G. Kazar, K. Koc, O.B. Tokdemir, Predicting Accident Outcomes in Cross-Border Pipeline Construction Projects Using Machine Learning Algorithms, Arab J Sci Eng. (2023) 1–19. https://doi.org/10.1007/s13369-023-07964-w.

[11]

I. Goodfellow, J. Pouget-Abadie, M. Mirza, B. Xu, D. WardeFarley, S. Ozair, A. Courville, Y. Bengio, Generative adversarial networks, Commun ACM. 63 (2020) 139–144. https://doi. org/10.1145/3422622.

[8]

F. Mostofi, V. Togan, Y.E. Ayözen, O.B. Tokdemir, Construction Safety Risk Model with Construction Accident Network: A Graph Convolutional Network Approach, Sustainability. 14 (2022) 15906. https://doi.org/10.3390/su142315906.

[12]

I. Goodfellow, J. Pouget-Abadie, M. Mirza, B. Xu, D. WardeFarley, S. Ozair, A. Courville, Y. Bengio, Generative Adversarial Networks, Commun ACM. 63 (2014) 139–144. https://doi. org/10.1145/3422622.

[9]

Z. Islam, M. Abdel-Aty, Q. Cai, J. Yuan, Crash data augmentation using variational autoencoder, Accid Anal Prev. 151 (2021) 105950. https://doi.org/10.1016/J.AAP.2020.105950.

[13]

M. Frid-Adar, E. Klang, M. Amitai, J. Goldberger, H. Greenspan, Synthetic data augmentation using GAN for improved liver lesion classification, Proceedings - International Symposium on Biomedical Imaging. 2018-April (2018) 289–293. https://doi. org/10.1109/ISBI.2018.8363576.

[10]

C. Zhou, R.C. Paffenroth, Anomaly detection with robust deep autoencoders, Proceedings of the ACM SIGKDD International Conference on Knowledge Discovery and Data Mining. Part F129685 (2017) 665–674. https://doi. org/10.1145/3097983.3098052.

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Research Bulletin No.8 September 2023

News and Events

Research Bulletin No.8 September 2023

News and Events News May 2023 - September 2023 • 18th May 2023

10th Undergraduate Research Competition (URC) at Abu Dhabi University Summary: Led by Dr Mustafa Batikha, and Yara Mouna, Mohd Saquib and Bushraa Irfan , Civil Engineering UG students from Dubai’s School of Energy, Geoscience, Infrastructure and Society were awarded 1st Place in the 10th Undergraduate Research Competition (URC) at Abu Dhabi University.

LinkedIn: https://www.linkedin.com/feed/update/urn:li:activity:7066651856395001856

• 1st June 2023

CES²C launches new strategy Summary: The Centre of Excellence in Smart and Sustainable Construction (CES²C) undertook an in-depth review of direction and operations to ensure that it best alignes with Heriot-Watt University’s strategic direction and with the opportunities and challenges presented by the UAE and MENA Construction sector.

This has included the launch of three core themes, Digital Transformation, Net Zero and Community Development.

For more information please visit: https://www.hw.ac.uk/dubai/research/smart-construction.htm

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Published articles May 2023 - September 2023 • 30th April 2023

CES²C Research Bulletin Seven Summary: CES²C published issue seven of its bi-annual Research Bulletin.

The bulletin included research articles focusing on the most recent trends in the Built Environment and was structured as per CES²C’s three innovation themes: Performance & Productivity, Sustainability, and Wellbeing.

Bulletin Link: https://issuu.com/heriot-watt_university_dubai/docs/cesc_bulletin_april_2023

• April 2023

Built Environment Middle East (E magazine) Summary: Dr. Harpreet Seth talks about what is needed for an equitable built environment to address challenges of global warming, space efficiency, and social and societal hurdles.

Full Article: https://www.mediafusionme.com/digital-magazines/builtenvironment/be-march-april2023/#page=16

• 1st May 2023

Built Environment Middle East Summary: Professor Lynne Jack shares a fascinating insight which takes an academic’s perspective on designing physical spaces that are inclusive, safe and sustainable for all users.

Full Article: https://www.mediafusionme.com/digital-magazines/builtenvironment/be-march-april2023/#page=21

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• June 2023

Facilities Management Middle East (print version) Summary: Dr. Hassam Chaudhry speaks about innovative technologies such asComputer-Aided Facilities Management (CAFM) and their implications in the sector.

• July 2023

MEP Middle East (print version) Summary: In this exclusive article, Dr Hassam Chaudhry shares his views on why sustainable building practices and green building designs hold immense significance in addressing current environmental, social, and economic challenges.

• July 2023

Construction Business News, Middle East (print version) Summary: Dr. Hassam Chaudhry shares his thoughts on vulnerability of construction sites to fire outbreaks and how it is one of the crucial reasons for focusing more on fire safety in construction projects, in an exclusive article for Construction Business News Middle East.

• 9th August 2023

Built Environment Middle East Summary: Dr Hassam Chaudhry shares his thought on how best we can optimise resources for energy efficiency at every stage of design in the Built Environment.

Full Article: https://www.builtenvironmentme.com/news/energy-waste-management/energyefficiency-and-the-built-environment

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Research Bulletin Bulletin Research No.8 September September 2023 2023 No.8

Events September 2022 – April 2023 • 9th May 2023

CES²C Webinar Summary: We were delighted to host a webinar entitled ‘En route to #cop28: Navigating the Legal Challenges of Sustainable and Smart Construction Innovations’ in conjunction with leading legal service providers, Al Tamimi and Company.

For More Information: https://www.youtube.com/watch?v=Zr5iKXE9dwA

• 30th May 2023

Construction Technology Festival 2023 Summary: Shameel Muhammed, Associate Professor, Heriot-Watt University and CES²C Committee Member gave his expert opinion on digital ways to deliver major projects greener, faster, cheaper, and more efficiently.at the Construction Technology Festival.

For More Information: https://www.linkedin.com/feed/update/urn:li:activity:7069204562636607488

• 16th June 2023

Emirates Green Building Council Annual Congress Summary: Dr Hassam Chaudry joined a panel which took a deep-dive into the important role sustainable Built Environment plays to accelerate climate action.

For More Information: https://www.linkedin.com/feed/update/urn:li:activity:7073905799764283393

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• 25th September 2023

ICE Webinar Summary: Dr Mustafa highlighted using plastic waste in concrete.

For More Information: https://www.eventbrite.com/e/plastic-concrete-bye-bye-plastic-wastetickets-716992542997

• 27th September 2023

Emirates Net Zero Forum Summary: Dr Mustafa Batikha joined the panel and shared his expert opinion at the Emirates Net Zero Forum, organised by the Advancing Net Zero Volunteering Team.

For More Information: https://www.linkedin.com/feed/update/urn:li:activity:7110527830123253760

Forthcoming Events • 30th November 2023

COP28

Summary: The Heriot-Watt University Climate Hub will be taking place at our Dubai campus between 30th November – 12th December. Please refer to our social media channels and website for details of the full event calendar.

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Research Research Bulletin Bulletin No.8 No.8 September September 2023 2023

CES²C Partners’ News Aldar Summary: Aldar investment properties issues usd 500 million 10-year inaugural green sukuk.

For More Information: https://www.aldar.com/en/news-and-media/aldarinvestment-properties-issues-usd-500-million-10-yearinaugural-green-sukuk

Jacobs Summary: Jacobs publish a report which takes a deep-dive in Transit – oriented development (TOD).

For More Information: https://www.jacobs.com/reports/cities-places/transitoriented-development?utm_source=social&utm_ medium=linkedin&utm_term=902df02d-88704511-b651-1686fd228c51&utm_content=&utm_ campaign=newsroom

JLL Summary: JLL publish a report which looks at the trends during Q2 2023 in the UAE Real Estate Market For More Information: https://www.jll-mena.com/en/trends-and-insights/ research/the-uae-real-estate-market-q2-2023

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Research Bulletin Bulletin Research No.8 September September 2023 2023 No.8

Mott Macdonald Summary: Mott Macdonald publish a case study which focuses on delivering the Musaimeer Pumping Station and Outfall Tunnel in Qatar.

For More Information: https://www.mottmacannualreview.com/case-studies/ digging-deep-to-guard-doha-from-climate-risk

Polypipe Summary: Polypipe Middle East publish a case study which focuses on elevating luxury living at Bulgari Resort and Residences.

For More Information: https://middleeast.polypipe.com/case-studies/elevatingluxury-living-bulgari-resort-and-residences

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