Research on Creep Model of Roadway Surrounding Rock Based on Variable Creep Parameters

In order to study the creep behavior of surrounding rock of Huaying Coal Mine in Sichuan under different confining pressure characteristics, the triaxial creep test of sandstone was carried out by TAW-2000 test system. Based on the improved Nishihara model, the model creep parameters are denormalized by introducing the relationship between damage variables and time. The improved variable parameter creep aging model is obtained. The results show that the time-dependent creep model with variable parameters can not only describe the attenuation creep and stable creep deformation characteristics of rocks, but also make up for the shortcomings that traditional creep models cannot describe accelerated creep characteristics. And it predicts the development of creep deformation well. The good agreement between the model and the test curve illustrates the correctness and rationality of the model.