Study on the Strength and Failure Behaviors of Sandstone Specimens at Elevated Temperature under Triaxial Compression

Deep rocks are in high geostress and high temperature environment, which makes the exploitation of deep resources face great challenges, so it is of great significance to study the triaxial mechanical behaviour of rocks under high temperature. This paper comprehensively adopts indoor test and numerical simulation methods to analyze the influence of real-time temperature and peripheral pressure on the strength and damage characteristics of sandstone, and reveals the law of rock thermal crack evolution. Firstly, triaxial compression tests on sandstone with different real-time temperatures were conducted and the influences of temperature and confining pressure on the mechanical properties of sandstone were obtained. Secondly, a three-dimensional numerical model of sandstone was constructed using PFC3D, and a set of microscopic parameters reflecting the mechanical behavior. of sandstone were calibrated by comparing with triaxial compression results at room temperature, on the basis of which a numerical simulation on sandstone under realtime high temperature triaxial compression was carried out, and the numerical results were consistent with the laboratory experimental results. The nume