考虑中间主应力对圆形巷道Hoek Brown准则解的影响

为了建立更加适用于深部巷道围岩塑性解分析的Hoek Brown准则，获得更加准确的巷道围岩塑性区范围及其支护变形量。通过将洛德参数表示的中间主应力带入Hoek Brown准则中，经过理论公式的推导，获得巷道围岩塑性区的应力和半径以及巷道周边位移的解析解。经算例分析，随着中间主应力的减小，塑性区范围也减小，当中间主应力趋近于第三主应力时，塑性区范围为最小；并且支护阻力和原岩应力对巷道塑性区范围也有一定影响；最后将计算的结果与Mohr-Coulomb准则对应的卡斯特纳解进行比较，发现文中建立的Hoek Brown强度准则更加适用于深部巷道塑性区分析。由此可知考虑中间主应力的Hoek Brown强度准则，更能全面分析巷道围岩塑性区的范围，获得更为准确的结果；在工程实践中，在易破坏的地段取地应力值时，应适当的增大中间主应力的取值，并且刚开挖巷道应及时支护，这样可有效的维护巷道围岩的稳定。

Hoek-Brown criterion solution of circular roadway with considering intermediate principal stress

In order to establish a more suitable Hoek-Brown criterion for analyzing deep roadway surrounding rock plastic solution,and then obtain the more accurate range of plastic zone and the supporting of roadway surrounding rock deformation,by taking the intermediate principal stress representing Lode parameters into Hoek-Brown criterion,through the deriving theoretical formula,the stress and radius of roadway plastic zone surrounding rock and roadway surrounding displacement were obtained. Through the example analysis,the scope of plastic zone decreases with the decreasing of intermediate principal stress,when the intermediate principal stress tends to be the third principal stress,the plastic zone is the minimum. The support resistance and pre-mining rock stresses have some influences on scope of roadway plastic zone. At last,comparing the results of calculation with kastner solution of Mohr-Coulomb criterion,it was found that the established Hoek-Brown strength criterion is more suitable for deep analysis on the plastic zone of roadway. So Hoek-Brown can analysis plastic zone range of roadway surrounding rock more comprehensive and accurate by considering the intermediate principal stress strength criterion. In engineering practice,crustal stress value of easily damaged location should be amplified,and immediate support should be conducted to early excavation roadway,so that the stability of the roadway surrounding can be effectively maintained.