Thermal damage of granite after thermal shock cycle

Abstract

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.

Temperature damage regularity of granite based on micro-inhomogeneity

“…While studying the change of rock mechanical properties under the action of temperature, the damage caused by temperature to rock is considered a very complex process, and it is closely related to the temperature and action of rock microstructure. Yu et al (2021a) researched the mechanical properties of granite under the influence of temperature through laboratory tests (Dong et al, 2020;Wang et al, 2021;Huang et al, 2022). The results show that the strength of granite decreases obviously with the temperature, and 400 °C is an obvious turning point.…”