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论文类型：会议论文

发表时间：2012-12-11

收录刊物：EI、Scopus

页面范围：703-707

摘要：Many concrete infrastructures are built on rock foundations, so the interfacial cracking behavior between concrete and rock is very important for the stability analysis of structures. Yet this issue is seldom addressed in literatures, which generally use theory of linear fracture mechanics to analyze interfacial cracking problems. Actually, the index of the singularity item of interfacial cracking is complex, instead of the constant 0.5 for homogeneous materials. In addition, the stress intensity factors K1 and K 2 are coupled, with no definite correspondence to tension or shear. So theory of linear fracture mechanics is no longer valid for such problems. Energy release rate of interfacial material is not a material constant, instead it is related to the mode mix angle   =a tan(K2/K1). In the presented paper, for the purpose of studying the interfacial cracking behavior of concrete/rock, four-point-shear-beam test is employed. The specimens are designed to be composed of two components, i.e., partly of concrete and the other part rock in the longitudinal direction. Prefabricated crack is introduced on one side of the interface and it's designed to propagate along the interface. The overall length of beams is constant, yet the length of each component is varied, so the location of prefabricated crack is varied, and this results in different angle    at the tip of the crack. As have been expected, most failure take place on the interface, but in some cases the crack kinks into the rock part and failure at the support is also observed. Based on the results corresponding to interfacial cracking, it's shown that with the increasing of angle   , implying longer concrete span and bigger shear component, (1) the maximum load decreases gradually; (2) CMOD decrease linearly; (3) CMSD increases at first and then decreases; (4) energy release rate decreases. ? 2013 Taylor & Francis Group.