深部巷道围岩分区破裂化数值模拟

Numerical simulation of zonal distrigation of surrounding rock mass in deep mine roadways

采用有限差分数值计算软件FLAC对巷道围岩分区破裂化进行研究,分析了分区破裂的产生及演化过程,即巷道开挖后,随着原岩应力的释放,多条破裂带从巷道表面或临近周边逐步向围岩深处延伸,在延伸过程中,单条破裂带可能会分叉成两条甚至多条破裂带,这些破裂带互相交叉,在巷道浅部围岩形成网状间隔破裂区,在深部围岩形成环带状间隔破裂区。岩体初始应力水平、侧压系数及巷道断面形状等对巷道围岩分区破裂化都有显著影响。数值模拟结果与前人的现场研究成果有很好的一致性。

The zonal disintegration of surrounding rock mass of roadway was investigated using finite difference code FLAC. The generation and evolution of zonal disintegration were analyzed as follows ： with the relaxation of initial stresses resulting from the excavation of roadway, numerous fracture ribbons extend from the surface and the vicinity of roadway to deeper fields of surrounding rock mass, within this process, one fracture ribbon may split in two or more fracture ribbons. These ribbons intersect with each other. Consequently, net fracture spacing is formed in the vicinity of roadway and ring fracture spacing formed in the deeper fields of surrounding rock mass. The level of initial stress before the roadway is excavated, as well as the lateral pressure and the section shape of roadway, all have significant effects on the characteristics of zonal disintegration. The results of numerical simulation are in good agree with the insitu monitoring results from former scholars.