Experimental Study on Uniaxial Mechanical Properties of Granite Under Thermo-liquid Coupling

In order to study the uniaxial mechanical properties and failure modes of granite under the condition of thermo-liquid coupling, the granite was subjected to thermo-liquid coupling cyclic treatment at different temperatures, and then its mechanical properties were analyzed by uniaxial compression test. The results reflect the following trends: (1) the stress–strain curve generally undergoes four stages, namely compaction, elastic deformation, yielding, and failure. (2) The peak intensity increases with temperature, decreasing by 11.51% when the temperature is in the range of 50–100 °C and decreasing by 1.77% when the temperature is in the range of 100–150 °C. The peak strain is fit by a linear relationship with the cycle temperature and decreases as the temperature increases. The modulus of elasticity first increases and then decreases with increasing temperature, increasing significantly by approximately 123.21%. (3) The peak intensity varies with the number of cycles and changes slowly before three cycles but changes obviously after three times. The peak intensity is reduced by 19.87% when the number of cycles is 3–4, and it is increased by 22.70% when the number of cycles is 4–5. The peak strain has a cubic fitting relationship with the number of cycles, and it is maximized at three cycles. The modulus of elasticity has a quadratic fit with the number of cycles, and it is minimized at three cycles. (4) In the contour map, the peak intensity is symmetrically distributed in three cycles when the temperature range is 50–100 °C.