Embodied carbon optimisation in structural design for one-way reinforced concrete slab

• Main Author: Wong, Ming Hao
• Other Authors: Teoh Bak Koon
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Engineering::Civil engineering
• Online Access: https://hdl.handle.net/10356/157903
• Institution: Nanyang Technological University

The environmental impact of construction is alarming as each project emits large amounts of waste and carbon dioxide, which lead to damaging effects on the environment and global warming. According to a new report published by the United Nations Environment Programme, the environmental (including carbon) footprint of the building sector consists of 40 % of energy use, 30 % of raw materials use, 25 % of solid waste, 25 % of water use, and 12 % of land use (SBCI, 2009). Fortunately, a great deal of effort has been put into reducing operational carbon emissions. However, as operational carbon reduction approaches its limit, it is about time for more efforts in reducing the embodied carbon of the buildings. According to the Institution of Structural Engineers (IStrucE), for every 20% reduction in structural embodied carbon, we can save up to 200,000 kgCO2e every year, which is a significant contribution compared to other major changes in the lifestyle of an average citizen. As such, this final year project aims to establish a guideline to assist structural engineers and relevant decision-makers in making environmentally conscious decisions during the early design stage. This project focuses on establishing a framework for the optimisation of the embodied carbon of slab design based on the slab design parameters (concrete strength, reinforcement ratio, dimensions, loading). The results showed that the optimum k-value to design the slab systems with the lowest is 0.167, due to the limit set in Eurocode 2 for singly reinforced It is also observed that longer slab spans and higher concrete strengths contribute to higher EC value. If the limit imposed by Eurocode 2 is ignored, based on the ductile failure theory, the optimum k-value for the lowest embodied carbon emission is higher than 0.167, ranging from 0.187 to 0.209, depending on the concrete strength used. The author believes that the findings can inspire engineers to find ways and strategies to optimise the use of concrete and steel for optimal sustainability when designing reinforced concrete structures.