Influence of cyclic loading on the tensile fracture characteristics of ultra-high performance engineered cementitious composites

Abstract Ultra-high performance engineered cementitious composite (UHP-ECC) with tensile strength of nearly 15 MPa and tensile strain capacity of nearly 8% exhibits high potential for improving the fatigue performance of modern infrastructures. In this study, monotonic loading tests were performed on UHP-ECC specimens subjected to different number of fatigue cycles and the influence of cyclic loading ratio on the fracture mechanism of UHP-ECC was investigated. In order to evaluate the effect of fatigue loading on the residual toughness of the material, the calculated pseudo strain-hardening (PSH) index was calculated for each loading mode. Furthermore, the fatigue tests at different stress levels were conducted and the corresponding relationship between stress level and fatigue life was compared with that published in literature. Based on the evolution of hysteresis curve, a fatigue damage prediction model was proposed. The thorough experimental investigations, combined with the numerical model, aim to provide useful reference for the future design of UHP-ECC structures subjected to repetitive loading.