Determination of tensile crack bridging of PCM-concrete interface subjected to fatigue loading by means of bending test

Abstract

In this paper, a simple and handy test method for determination of the tensile crack bridging law of PCM-concrete interface is proposed. Based on the fatigue failure mechanism of PCM-concrete interface that is governed by crack propagation as the result of interface bridging degradation, the J-integral method proposed for determining the tension softening relation of concrete under static loading is modified to determine the PCM-concrete interface tensile stress degradation relation. The derived degradation relation is compared to that of normal concrete under cyclic uniaxial tensile tests, and it can be found that the PCM-concrete interface has higher degradation rate so that more attention should be paid to the PCM-concrete interface during the design of PCM-retrofitted structures under fatigue loading.