Development of green engineered cementitious composites with acceptable dynamic split resistance utilising recycled polymer fibres

Using recycled tyre polymer fibres (RTPF) to replace part of polyvinyl alcohol fibres (PVAF) is a strategy to produce green and economical engineered cementitious composites (ECC). This paper systematically investigated the influence of RTPF dosage (0.25-1.0 vol%) on split tensile performance of ECC under different strain rates. Results indicated that replacing PVAF with RTPF up to 0.5 vol% could still show a pronounced strainhardening behaviour for ECC, although accompanied by a decrease in static split tensile strength. The dynamic split tensile performance of all ECC mixes was strongly sensitive to strain rate and all hybrid fibre reinforced ECC presented a greater strain rate effect than the mono-PVAF reinforced ECC. Under dynamic split tension, the specimens with various RTPF dosages could maintain their structural integrity. This paper suggested that RTPF can be adopted to replace part of PVAF to produce a greener and more economical ECC with satisfactory static and dynamic mechanical performance but the highest substitution amount should be set to 0.5 vol %.