A Study of Rock Crack Fracture under Different Temperatures

A series of critical fracture toughness of two kinds of rock materials under different temperature which varied from-50°C to 240°C are measured by I-II-III mixed mode fracture experiments adopting atypical three point bending specimens. Relative stress intensity factors of crack initiation are calculated by finite element method. Combining with calculated values, the experiment results show that, the mixed mode fracture toughness of the rocks decreases with the increase of temperature. The experimental and calculated results can be used in the design of deep underground engineering or disaster prevention and mitigation engineering.