【目的】为了定量探究岩石受热作用损伤的过程。【方法】从能量角度出发,通过冷却法研究实验室尺度下不同尺寸类型花岗岩试件在空气中冷却时热物理参数演变规律,讨论花岗岩受非稳态传热全过程能量吸收、能量释放及能量耗散特性,揭示非稳态过程中能量演变规律与花岗岩试件尺寸特征的内在联系。【结果】结果表明:不同尺寸类型高温花岗岩试件空冷至室温的过程中,比热持续降低;非稳态传热能量演变过程中,同一种尺寸试件耗散能与耗散比的大小与初始高温状态呈正相关;花岗岩在非稳态传热条件一致的情况下,随试件体积的增大,用于损伤的这部分能量绝对值在增加但相对值在减小;随着试件比面的增大,用于损伤的这部分能量绝对值在减小但相对值在增大。研究结果能够丰富高温岩石力学理论研究的发展。

【Purposes】The damage of rocks by thermal action is an extremely common natural  and engineering phenomenon.【Methods】The evolution of thermophysical parameters of granite speci⁃ mens of different sizes cooled in air at laboratory scale is studied from the energy point of view through  the cooling method, and the characteristics of energy absorption, release, and dissipation during the  whole process of unsteady heat transfer are discussed to reveal the intrinsic connection between the  evolution of energy in the unsteady process and the size characteristics of granite specimens.【Find⁃ ings】 The results show that: The specific heat of different sizes and types of high-temperature granite  specimens continues to decrease in the process of air cooling to room temperature; In the process of  unsteady state heat transfer energy evolution, the magnitudes of the dissipation energy and dissipation  ratio of specimens with the same size are positively correlated with the initial high-temperature states;  In the unsteady state heat transfer conditions are consistent, with the increase in the volume of the  specimen, the absolute value of the energy used for damage is increasing but the relative value is de⁃ creasing;With the increase of specimen specific surface, the absolute value of the energy used for dam⁃ age is decreasing but the relative value is increasing. The results of this study can enrich the develop⁃ ment of high-temperature rock mechanics theory.