Thermal damage of granite after thermal shock cycle

This paper reports the tensile strength and P-wave velocity of granite after cyclic high temperature and thermal shock, and calculates the thermal damage by tensile strength and P-wave velocity to explore a general method for evaluating thermal damage. The results show that thermal damage of granite is strongly correlated with temperature and cycle, and it increases with the increase of temperature and thermal shock cycle. There is a good exponential correlation between the damage calculated by tensile strength and P-wave velocity. Thermal damage is mainly caused by the expansion of mineral grains and the formation of cracks. Thermal shock cycle accumulates thermal damage of granite and eventually causes the critical temperature threshold of rock damage to decrease to 350°C and even to 250°C.