Sustainability analyses of embodied carbon and construction cost in high-rise buildings using different materials and structural forms

ABSTRACT

Understanding the impact of material choices and structural forms on the embodied carbon and construction cost in high-rise buildings is important to improve building designs with regard to sustainability. The objective of this study is to investigate the impact of the choice of construction materials and structural forms on the embodied carbon and construction cost of high-rise buildings. The results show that high-rise buildings using structural steel have the highest construction cost at 4575 HK$/m² and the most embodied carbon at 760 kg CO₂-e/m², respectively. Using reinforced concrete for high-rise buildings reduces 30% of the embodied carbon (to 4194 HK$/m²) and 7% of the construction cost (to 537 kg CO₂-e/m²). High-rise buildings using composite materials have the lowest construction cost (3740 HK$/m²), but produce slightly more embodied carbon (557 kg CO₂-e/m²) than concrete buildings. For a specific structural form, the construction cost and the embodied carbon as a function of the building height follow concave upward trends, indicating that each structure has a suggested height with relatively lower cost and carbon content, e.g. 50–70 storeys for composite core-outrigger structure at around 3700–3900 HK$/m². Similarly, the suggested height for composite tube-in-tube structure is 60–80 storeys at 3900–4100 HK$/m², whereas braced-tube structure has a suggested height of 60–80 storeys at 3500–3600 HK$/m².

KEYWORDS:

• Construction cost
• construction material
• embodied carbon
• high-rise building
• structural form

Acknowledgement

The authors are grateful to Dr Goman W H Ho, Director of Ove Arup & Partners Hong Kong Ltd., for his valuable discussion and technical support on the structural design of Cheung Kong Center in Hong Kong, which was used as a reference for designing the high-rise buildings in this study.

Additional information

Notes on contributors

Vincent J L Gan

Dr Vincent J L Gan is a Research Assistant Professor in the Department of Civil and Environmental Engineering at The Hong Kong University of Science and Technology (HKUST). He received dual bachelor degrees from China University of Geoscience (CUG) and Huazhong University of Science and Technology (HUST), and then obtained his M.Sc. and Ph.D. degrees from the HKUST. His research interest includes life cycle carbon measurement, embodied carbon of construction materials, building energy modelling, low carbon design of tall buildings and construction informatics. Dr Gan has good interdisciplinary background and intergroup research experience. He has carried out studies on low carbon construction materials and structural forms for tall buildings, considering the wind-driven impact. His recent research focuses on the use of building information modelling (BIM) for the design and optimisation of low carbon high-rise buildings.

C M Chan

Prof C M Chan is currently a Professor in the Department of Civil and Environmental Engineering at the HKUST. He received his B.Sc. and M.Sc. degrees from Massachusetts Institute of Technology in 1984 and 1985, respectively, and also Ph.D. degree from the University of Waterloo in Canada in 1993. His current research interests include structural optimisation, tall building analysis and design, sustainable development of green buildings, wind effects on structures and sustainable wind energy. He has received a number of research and teaching awards, including the 1998 State-of-the-Art Civil Engineering Award by the American Society of Civil Engineers, the 2014 Michael G. Gale Medal for Distinguished Teaching of the HKUST. He has authored or co-authored more than 130 technical papers and research reports published in professional books, journals and/or the proceedings of national and international conferences.

K T Tse

Prof K T Tse is currently an Associate Professor in the Department of Civil and Environmental Engineering at the HKUST. He received his Ph.D. degree in Wind Engineering in 2009 from the HKUST. His research interests include wind-induced dynamic loads, building aerodynamics and wind-resistant analysis of tall buildings. He has published over 100 refereed journal papers, peer-reviewed conference papers and consulting project reports. In 2016, he received the IAWE Junior Award, conferred by the International Associate for Wind Engineering in recognition of achievements and pioneering contributions to dynamic wind load effects on structures and wind-resistant analysis of tall buildings. He is a Founding Committee Member of the Hong Kong Wind Engineering Society and has served as the Vice-Chairman since its establishment in 2011. He was invited by the Buildings Department of the HKSAR Government in 2012 and served as a Steering Committee Member of two Technical Committees: the Code of Practice on Wind Effects in Hong Kong and the Code of Practice on the Structural Use of Glass. He is a member of The Australasian Wind Engineering Society, American Association for Wind Engineering, Hong Kong Wind Engineering Society and European Mechanics Society.

Jack C P Cheng

Prof Jack C P Cheng is currently an Associate Professor in the Department of Civil and Environmental Engineering at the HKUST. He obtained his Bachelor degree with First Class Honours and his MPhil degree from the HKUST, and then obtained his Ph.D. degree from Stanford University. His research interests include BIM, green buildings, sustainable construction, carbon auditing, Internet of Things (IoTs), construction informatics and management and laser scanning. Prof Cheng is currently the Vice-Chair of the American Society of Civil Engineers (ASCE) Global Center for Excellence in Computing, the Treasurer and Director of ASCE Hong Kong Section, a Certified Carbon Auditor Professional, a Professional Member of The Hong Kong Institute of Building Information Modelling (HKIBIM), and the Editor or Editorial Board Member of several journals. He has authored or co-authored over 130 refereed journal and conference papers. He has received the Young BIMer of the Year BIM Excellence Award 2014 from the Construction Industry Council of Hong Kong, and several paper awards in international conferences.

Irene M C Lo

Ir Prof Irene M C Lo is currently a Chair Professor in the Department of Civil and Environmental Engineering at the HKUST. She has been joining the HKUST since 1992. Ir Prof Lo is an elected Academician of the European Academy of Sciences and Arts (EASA). She is the first Hong Kong scholar inducted into the EASA. She is a Fellow of The Hong Kong Institution of Engineers (FHKIE), and elected Fellow of the ASCE (FASCE). She received her Ph.D. degree in Civil (Environmental) Engineering from the University of Texas at Austin in 1992. Ir Prof Lo was the recipient of the 2004 ASCE James Croes Medal, the 2007 ASCE Samuel Arnold Greeley Award, the 2008 EWRI Best Practice-Oriented Paper Award, the 2009 ASCE Wesley W Horner Award and the 2012 ASCE EWRI Best Practice-Oriented Paper Award. Her research areas include solid waste/construction & demolition waste/wastewater treatment and management, green buildings, life cycle assessment and carbon audit.