Review on recent advances of sustainable engineered/strain-hardening cementitious composites (ECC/SHCC) with ultrahigh-volume pozzolan

Engineered Cementitious Composites (ECC, also known as Strain-Hardening Cementitious Composites or SHCC) are a family of high-performance fibre-reinforced cement-based materials. With the ultimate tensile strain of over 1% and the self-controlled crack width of less than 100 μm, ECC enables high damage tolerance and outstanding durability under various environments for infrastructure. Owing to the absence of coarse aggregates and the low content of fine aggregates, the cement content in conventional ECC can be over 600 kg/m3, which is undesirable for low-carbon buildings and infrastructure. Ultrahigh-volume (over 60%) pozzolan has been explored to produce sustainable ECC. This article reviews recent advances of sustainable ECC with ultrahigh-volume Class F fly ash or limestone calcined clay. These sustainable ECC either match or surpass mechanical properties and durability characteristics of conventional ECC, while their carbon footprint and embodied energy are much lower than those of conventional ECC. This review article sheds light on fundamental and applied studies on sustainable ECC.