ABSTRACT
The construction industry is a major producer of CO2 emissions. The significant impact of the construction industry largely arises from the embodied carbon in the primary construction materials, cement and steel. In a tunnelling project, it is generally considered that 60% to 70% of embodied carbon is contained in the concrete linings of the shafts and tunnels. It is paramount, therefore that the tunnelling industry should promote sustainable design. Fiber reinforcement plays a vital role in reinforcing concrete linings in underground structures and tunnels. This paper will explain how High-performance steel fiber reinforcement over rebar, combined with structural design optimization and the utilization of Supplementary Cementitious Materials (SCM) concrete mixture, the embodied carbon in the segmental lining and permanent spray concrete lining can be reduced by nearly fifty percent. Over the past years the use of Fiber Reinforced Concrete (FRC) for finagling has increased dramatically. One aspect allows the boosting the use of FRC was the publication of guideline for FRC design: in 2012, the international Federation for structural concrete (fib) presented Model Code 2010 which include specification section on FRC. the Mode code 2020 just published has led to a successful and now widespread use of FRC in the final lining tunnelling with considerable benefits to owners, designers, and contractors. This paper will describe design principle and detail carbon counting from recent project around the world in Europe Middle east, North America and Singapore.
