EXPERIMENTAL INVESTIGATION ON FRACTURE TOUGHNESS OF INTERFACE CRACK FOR ROCK/CONCRETE

Abstract

Fracture toughness is a critical input parameter for fracture-mechanics based fitness-for-service assessments, and it is preferable to determine this by experiment. In the present paper, fracture toughness of rock/concrete bimaterial interface was obtained by the tests which were performed on the universal material tester. A beam specimen with single-edge crack is used to form the different fracture mode mixity. The stress intensity factors of specimen per unit load with different combinations of K1 and K2 were calculated by the mixed hybrid finite element method on the principals of linear elastic interface fracture mechanics. By regressing the critical stress intensity factors of 7 specimen groups, two experiential fracture criterions of mixed crack interface were derived, and the fracture toughness([Formula: see text], [Formula: see text]) of rock/concrete were obtained further.