Mechanical properties of high ductility hybrid fibres reinforced magnesium phosphate cement-based composites

Abstract

Polyvinyl alcohol (PVA) fibres were mixed with polypropylene (PP) fibres or micro-steel (MS) fibres, and then were added into MPC to improve its mechanical properties in this study. The influences of fibre hybrid schemes on the workability and mechanical properties of MPC-based composites were investigated experimentally. The crack characteristics of specimens with various fibre hybrid schemes were classified. Moreover, the microstructure of hybrid fibres reinforced MPC-based composites was further assessed using scanning electron microscopy (SEM). The experimental results show that the PVA fibres can well bridge the micro-cracks and improve the ductility index as well as the toughness index of MPC-based composites, and the MS fibres can effectively enhance the compressive and flexural strengths of MPC-based composites. PP fibres have no significant effect on the strength and deformability of the MPC-based composites in the hybrid system. The PVA and MS fibres can effectively work together to improve both the ductility and strength of MPC-based composites. Based on the current study, by adding 1.6% PVA and 0.6% MS fibres into the MPC, the compressive strength and flexural strength increases by 12.7% and 25.7%, respectively, as compared to MPC with 1.6% PVA fibres. Besides, the toughness index of the specimens increases by 26.9% and the bending performance is significantly improved.