关键词: 高温劣化, 页岩, 力学性质, 单轴压缩试验, 数值模拟

Abstract: The black shale samples of Niutitang Formation of the Lower Cambrian in the northern Guizhou region were tested under a 1011BS electric blast drying oven simulated high-temperature environment by the RMT-301 loading system. The uniaxial compression tests were performed on shale samples at different heating temperatures. A numerical model using the real rock fracture analysis system RFPA2D Thermal was established to simulate the fracture process of the shale at the same temperature. The results indicate that the temperature significantly affects the compressive strength of the shale sample. Starting from the room temperature, as the temperature increases, the maximum acoustic energy, the brittleness, and the peak intensity of the shale samples continue to increase, reaching their highest value at 120 ℃. Afterwards, as the temperature increases, these parameters decrease. The occurrence of the macroscopic cracks in shale samples at 200 ℃ after the temperature treatment, which propagate and penetrate during the uniaxial compression, is an important reason for their severe strength degradation. 

Key words: High Temperature Degradation, Shale, Mechanical Properties, Uniaxial Compression Tests, Numerical Simulation