旗山矿水平岩层软岩巷道破坏过程物理模拟研究

Physical simulation study on failure process of horizontal strata soft rock roadway in Qishan Mine

针对深部复杂工程岩体变形破坏的力学行为,以水平层状沉积岩体作为物理模拟的研究对象,开展了软岩巷道变形破坏过程物理模拟试验,研究了水平岩层软岩巷道的裂纹扩展及变形破坏特征。以旗山矿-1 000 m水平轨道联络大巷的地质资料为背景,在试验过程中对模型内部的应力变化进行实时监测,并采用摄像机跟踪记录整个模型的变形过程。结合模型内部关键点的应力场以及试验照片分析了巷道破坏过程中裂纹产生和扩展过程。结果表明:水平岩层软岩巷道在自重应力和构造应力作用下先在底板处产生裂纹,然后在两帮和顶板处产生裂纹,裂纹随荷载增大而扩展并贯通导致巷道整体破坏。

For recognizing deep engineering complex rock mass deformation and failure mechanical behavior, taking horizontal stratified sedimentary rock masses as the research object, the authors carried out physical modeling experiment to study the deformation and crack propagation characteristics of horizontal stratified soft rock roadway. The field background for the experiment was main connecting tunnel located at depth of-1 000 m in Qishan Mine. The variation of in-plane stress of the model rock mass was measured and deformation process was recorded by a video camera simultaneously. Crack initiation and propagation process during the test was analyzed based on the video photos and the stress of the key monitoring points was analyzed based on the measured stress data sets. The experimental results showed that under the gravity stress and tectonic stress, crack initiation occurred at the bottom of the roadway at first. Then the cracks ap- peared on the side and top of the roadway. Ultimately a complete failure of the roadway occurred due as coalescence of the propagating cracks under the increasing loads.