巷道围岩破碎区分布特征及其影响因素的数值模拟
Investigation on the characteristics of excavation damaged zone and numerical simulation of contributing facotrs
-
摘要: 基于圆形巷道经典松动圈解析解进一步推导了破碎区范围的分布特征, 分析了围岩破碎区与巷道断面、侧压系数、埋深等因素的关系, 评价了围岩稳定性。研究结果表明:巷道断面形态对围岩破碎区范围的影响较小;侧压系数<1.0时, 巷道的两侧易发生失稳破坏;在侧压系数等于1.0时, 巷道围岩破碎区分布最为均匀, 巷道处于相对稳定的状态;侧压系数>1.0时, 巷道顶底板处则较巷道两侧易发生失稳破坏;围岩破碎区范围随着埋深的增加而增大, 在埋深为1 500 m时, 巷道围岩达到了极限强度, 从而认为巷道开挖存在一个极限埋深。Abstract: Based on the analytical solution of excavation damaged zone in traditional circular roadway, the distribution characteristics of excavation damaged zone are further deduced.The relationship between excavation damaged zone and the roadway section, the lateral pressure coefficient and the depth of the roadway is analyzed.Also, the stability of surrounding rock is evaluated.The results show that the cross section of the roadway has little effect on the variation of excavation damaged zone of the surrounding rock.When the lateral pressure coefficient is less than 1.0, both sides of the roadway are prone to destabilized damage.When the lateral pressure coefficient is equal to 1.0, the excavation damaged zone of the surrounding rock is the most stable and the roadway is in a relatively stable state.When the lateral pressure coefficient is more than 1.0, the roof and floor of the roadway are prone to destabilized damage.The range of surrounding rock excavation damaged zone increases linearly with the increase of depth.When the depth is 1 500 m, the surrounding rock reaches the ultimate strength, so that there is a limit for buried depth in roadway excavation.