Dynamic tensile behaviour of high performance fibre reinforced cementitious composites after high temperature exposure

The uniaxial tension behaviour of high performance cementitious composites subjected to high strain rates after high temperature exposure has never been investigated. The material investigated was a steel fibre reinforced mortar. Straight low carbon steel micro-fibres were used. The fibre content was 1.25% by volume and the mix design guaranteed a self compacting mixture. The main purpose of the research was to highlight the role of thermal damage in uniaxial tension at low and high strain rate loadings. Looking in particular at peak strength and post-peak toughness the results show that, in low strain rate tests after high temperature exposure up to 600 °C, the thermal damage progressively reduces the toughness and weakly increases the strength; at high strain rate the peak strength significantly increases in comparison with low strain rate one for all the temperature investigated, while the toughness for growing temperature progressively decreases.

► We performed static and dynamics tests on HPFRCC material.
► We studied the influence of strain rate and high temperature on the HPFRCC material.
► HPFRCC show a high value of DIF up to 400 °C for all the strain rates investigated.
► Dissipated energy in damaged HPFRCC remains almost constant for growing strain rate.
► HPFRCC exposed to 600 °C fails due to fibre rupture and changes in matrix structure.