Effect of cyclic exposure and fibre content on tensile properties of ultra-highperformance concrete

This paper reports the results of experimental work conducted to study the effect of wet-dry and heating-cooling cycles and fibre content on tensile properties of a commercially available mixture of ultra-high-performance concrete (UHPC). The tensile properties of UHPC specimens are determined using two commonly used tests: the split tensile test and flexural test. Prisms are used in flexural tests to determine modulus of rupture, flexural toughness and postcracking flexural strength. Flexural test results show that after reaching the cracking load, the specimens continue to carry more loads with an increase in deflection until the peak load is reached. Following the attainment of peak load, softening mode of collapse is noticed, exhibiting high ductility. UHPC mixtures containing fibres show no degradation in tensile properties under wet-dry cycles and modestly gain strength under thermal cycling, indicating the possibility of the applications of UHPC in aggressive exposure conditions.