关键词: 洛河组砂岩, 类裂隙岩石, 解冻, 三轴压缩蠕变, 蠕变模型

Abstract: The main inclined shafts of some coal mines in sandstone strata of Fushuiluohe Formation are constructed by artificial freezing method, and the surrounding rock of the inclined shaft wall will undergo creep failure under long-term stress after thawing. In order to study the creep failure mechanism of rocks with different fracture dip angles after thawing, taking the sandstone of Luohe Formation in a mine as the original rock, the sandstone-like rocks with prefabricated fractures of different angles were prepared, and the mechanical properties of triaxial compression creep after thawing were studied. The experimental results show that : Among the three inclination angles of sandstone-like prefabricated, when the inclination angle is 45°, the development and expansion of internal new cracks along prefabricated cracks are greater, and the generated axial creep is larger and the change rate is faster. The second is fracture dip angle 0°, the last is fracture dip angle 75°. According to the test results, based on the Nishihara creep model, the fractured plastic body elements and the degradation evolution equation of the whole creep process are introduced to establish a nonlinear creep model considering the influence of the original joints and carry out a three-dimensional extension. The least square method is used to solve and fit, and the fitting results are basically consistent with the experimental data. The research results have certain reference value for disaster mechanism analysis and long-term safety evaluation of artificial freezing inclined shaft after thawing.