上行卸压开采顶板裂隙带巷道失稳过程物理模拟

Physical simulation of roof fractured zone roadway instability in ascending de-stressed mining

为解决上行卸压开采顶板裂隙带巷道大变形问题,采用物理模拟方法,研究上覆岩层活动特征及裂隙发育破坏过程,分析锚杆支护条件下巷道围岩应力变化过程及变形破坏特征。结果表明:顶板裂隙带巷道随着上覆岩层有整体下沉特征;上行开采采动影响阶段,在采动应力与巷道掘进围岩应力叠加形成的应力场和采动裂隙场共同作用下,顶板裂隙带巷道围岩强度大幅降低,巷道断面收敛变形强烈,采动影响稳定阶段围岩应力低,用锚架联合支护或注浆加固围岩技术手段能维护巷道断面,保证其安全使用。

In order to solve the problem of large deformation of roof fractured zone roadway maintenance in ascending de-stressed mining,overlying strata movement characteristics and fracture failure process were researched by using the method of physical simulation. Meanwhile roadway surrounding rock stress and failure characteristics under the condition of boltsupport were analyzed.The results show that roof fractured zone roadway falls down coordinating with the overlying strata,that at the stage of workface mining,strength of surrounding rock of roof fractured zone roadway drops sharply accompanied by the severe roadway convergency,because of interactions between fracture field and superimposed stress field of mining and roadway extraction,that when the interaction becomes steady after workface mining,surrounding rock stress declines,and that the bolting combined with U-steel or grouting can be implemented to support the roadway.