Mechanical properties of macro synthetic fiber reinforced concrete at elevated temperatures: A systematic review and meta-analysis

The current infrastructure boom combined with the latest outcomes from 26th UN Climate Change Conference of the Parties (COP 26) seeking a carbon neutral society by 2050 have driven the increasing need for sustainable alternatives to be considered in construction. One such alternative is macro synthetic fibers, which have been gaining acceptance on major infrastructure projects. However, only limited uptake has occurred in permanent structures, due to a lack of knowledge around the behavior of macro synthetic fiber reinforced concrete (MSFRC) when exposed to elevated temperatures. Existing Australian and international design standards do not take into account the loss of strength for MSFRC after exposure to elevated temperatures. Hence, this systematic review sets out to combine all the existing knowledge on the mechanical properties of MSFRC and lay the groundwork for determining acceptable relationships between relative strengths and elevated temperatures. This study proposes relationships between temperature and compressive strength, splitting tensile strength, elastic modulus, flexural strength and residual flexural, and tensile strengths of MSFRC. These are compared to existing relationships determined for plain concrete and steel fiber reinforced concrete to position MSFRC within the context of existing and accepted knowledge.