圆形巷道围岩破坏机制解析及静动耦合响应力学行为

非等压圆形巷道围岩塑性区相关问题是影响围岩破坏失稳的重要因素。首先，基于Mohr-Coulomb破坏准则，分析非等压圆形巷道围岩塑性区边界条件，探究侧压系数对塑性区形成的影响机制。此外，利用ANSYS/LS-DYNA仿真平台对不同侧压系数下的巷道围岩力学行为进行静动载荷耦合响应数值模拟。结果表明：侧压系数的增大显著改变围岩有效应力的分布特征。有效应力场的分布特性与塑性区边界理论解具有一定的吻合性。不同侧压系数的应力场作用时，巷道围岩的变形具有显著的差异性，随着侧压系数的增大，围岩发生较大的非均匀性变形。静动耦合作用下顶板和底板的围岩破坏区域显著增加，但两帮围岩的破坏面积有减小的趋势。

Analysis of Failure Mechanism and Mechanical Behavior of Static and Dynamic Coupling Response of Surrounding Rock of Circular Roadway

Abstract: The related problems of surrounding rock plastic zone in non-isobaric circular roadway are important factors affecting the surrounding rock failure and instability. Firstly, based on Mohr-Coulomb failure criterion, the boundary conditions of plastic zone in non-isobaric circular roadway were analyzed, and the influence mechanism of lateral pressure coefficient on the formation of plastic zone was investigated. In addition, ANSYS/LS-DYNA simulation platform was used to simulate the static and dynamic load coupling mechanical response behaviour of the roadway surrounding rock under different lateral pressure coefficients. The results show that the increase of lateral pressure coefficient significantly changes the distribution characteristics of the effective stress in the surrounding rock. The distribution characteristics of the effective stress field are consistent with the theoretical solution of the plastic zone boundary. There is a significant difference in the deformation of roadway surrounding rock under the action of the stress field with different lateral pressure coefficient. As the lateral pressure coefficient increases, a large non-uniform deformation occurs in surrounding rock. The surrounding rock failure area of the roof and floor increases significantly under static and dynamic coupling, but the surrounding rock failure area of the two sides tends to decrease.