TENSILE PERFORMANCE OF HIGH PERFORMANCE PVA FIBER REINFORCED CEMENTITIOUS COMPOSITES UNDER UNIAXIAL TENSION

HPFRCC with high toughness has high energy absorption capability, but strength is often relatively low. By using the local material resource and industrial waste, HPFRCC were prepared, which has high strength and deformation meeting the practical engineering need. It can be applied to the key positions of tall earthquake-resistant structures. Based on experiments for strength and deformation under uniaxial tension, the influences of PVA fiber content by volume, fly ash and silica fume content, water to binder ratio and sand binder ratio on tension performance of HPFRCC were studied. Study results indicate that as PVA fiber content by volume increases, the tensile strength and ultimate tensile strain of HPFRCC increase. High volumes of fly ash replacement of cement and increasing water to binder ratio reduce tensile strength of HPFRCC, but significantly improve its tensile strain hardening characteristics. While incorporating the right amount of silica fume and fine sand, tensile strength of HPFRCC can increase, but tensile strain reduce. Especially when the sand binder ratio is high, tensile strain hardening phenomenon of HPFRCC is not obvious. Based on the micro-mechanical model, the causes of influence factors on tensile strain hardening properties of HPFRCC are also analysed. The study can serve as a foundation for the practical engineering application of HPFRCC.