Study on the mechanism of mechanical property strengthening of Beishan granite under mild temperature condition

Micro‐Thermomechanical Modeling of Rocks With Temperature‐Dependent Friction and Damage Laws

“…where β T L is the linear thermal expansion coefficient of porous matrix, while T 0 and T are the reference and actual ambient temperature. Note that no significant mineral component transformation occurs in rocks such as granite and marble under a relatively mild temperature range, c.f., T ⩽ 200°C (Zhong, 2017;F. B. Yang et al, 2022).…”

“…Particularly, within a relatively mild ambient temperature range, the friction coefficient of rocks exhibits temperature-strengthening properties (Hu & Sun, 2020;L. N. Y. Wong et al, 2020;F. B. Yang et al, 2022).…”

“…Note that no significant mineral component transformation occurs in rocks such as granite and marble under a relatively mild temperature range, c.f. , T ⩽ 200°C (Zhong, 2017; F. B. Yang et al., 2022).…”

“…Recently, however, a series of investigations have revealed that the friction coefficient is not a constant material parameter; rather, it is dependent on a number of factors, for example, ambient temperature, stress state, moisture, damage state, friction rate, and spatio‐temporal scale (Ben‐David & Fineberg, 2011; Putelat et al., 2011; Scholz, 2019; Zhang & Ma, 2021; C. X. Zhao, Liu, et al., 2023; Thom et al., 2023). Particularly, within a relatively mild ambient temperature range, the friction coefficient of rocks exhibits temperature‐strengthening properties (Hu & Sun, 2020; L. N. Y. Wong et al., 2020; F. B. Yang et al., 2022). As temperature increases, the inhomogeneous inherent thermal expansion of minerals leads to greater contact area and enhanced occlusion interactions between rock particles; meanwhile, the loss of free and crystal water resulting from heating also contributes to the microroughness increment (Guo et al., 2023; H. T. Yang et al., 2013; Zhong, 2017).…”