Fracture Behavior of Brazilian Disc Specimens Containing Fissure-Holes Based on the FEM-CZM Method
摘要
Fissure and holes, including their shape and combinatorial distribution, significantly influence the tensile performance in rocks. In this paper, the tensile behavior of Brazilian disc specimens containing fissure-holes was investigated based on the FEM-CZM method. Firstly, the numerical parameters were obtained by the comparison with the previous results of Brazilian disc specimens containing a single fissure. Subsequently, the effect of distribution characteristics of fissure-holes on the fracture behavior the Brazilian disc was studied. Finally, the mechanical properties were discussed. The results indicate that tensile forces primarily induce cracks around the fissures, and the tensile strength varies nonlinearly with the fissure inclination and rock bridge length. Specifically, cracks generally initiate at the fissure tips, and secondary cracks form at the specimen boundaries and square holes. The overall tensile strength of rock specimens containing fissure holes increase with increasing fissure inclination and rock bridge length. The tensile strength varies nonlinearly with the rock bridge inclination. The effect of different combinations of holes on the tensile strength of rock specimens is relatively small. This research contributes to the understanding of the fracture behavior of rocks with complex defects and has important implications for improving material design and testing methods.