Mixed mode fracture of cementitious bimaterial interfaces; Part I: Experimental results

An experimental investigation on the mixed mode response of concrete interfaces is reported. Large simulated rock/concrete bimaterial specimens are subjected to the complex stress field that exists along a dam/foundation interface. Based on the observed crack trajectory, and on the recorded loads and displacements, important qualitative conclusions are drawn. It was observed that a crack which initiates at the interface is likely to kink into the adjoining rock when subjected to mixed mode loading as in a dam, and that the overall interface strength is only slightly affected by the curvilinear crack