考虑峰后软化的圆形巷道稳定性分析及工程应用

为获得更准确的巷道围岩应力分布和变形特征，基于统一强度理论，考虑围岩塑性软化和中间主应力的影响，引入塑性软化参数，推导出巷道围岩弹塑性区应力、塑性区范围和位移的表达式。通过算例分析，得到塑性软化系数和中间主应力等相关参数对巷道围岩应力分布、塑性区半径和位移的影响规律。研究结果表明:随内摩擦角软化系数和黏聚力软化系数的增大，围岩塑性区半径和位移呈现先急剧后缓慢的减小趋势；中间主应力系数对巷道围岩弹塑性应力有着显著影响，中间主应力系数越大，围岩塑性区半径和位移越小。

Stability analysis and engineering application of circular roadway considering post-peak softening

In order to obtain the stress distribution and deformation characteristics of the roadway surrounding rock more accurately, based on the unified strength theory, the expressions of the elastic-plastic zone stress, plastic zone range and displacement of the roadway surrounding rock were deduced by considering the surrounding rock plastic softening and the intermediate principal stress, with introducing into the plastic softening parameter. The influence laws of the relevant parameters, such as the plastic softening coefficient and the intermediate principal stress, on the stress distribution, the radius and displacement of plastic zone in roadway surrounding rock were concluded through the example analysis. The results showed that the radius and displacement of plastic zone in surrounding rock presented a decreasing trend being sharp first and then slow with the increase of the internal friction angle softening coefficient and the cohesion softening coefficient. The intermediate principal stress coefficient had a significant influence on the elastic-plastic stress of the roadway surrounding rock, the greater the intermediate principal stress coefficient, the smaller the radius and displacement of plastic zone in surrounding rock. The correctness of the analytical solution was verified by comparing the numerical simulation results with the field measurement data. The research results can provide a certain theoretical basis for the supporting design and stability analysis of the roadway surrounding rock.