基于离散元的顺倾节理岩质边坡破坏过程分析

Failure Mechanism of Inclination Joint Rock Slope Based by Discrete Elements Method

为了研究含顺倾节理岩质边坡的破坏过程,以某露天矿西南区域边坡为研究对象,建立典型剖面的数值模型,并通过室内试验标定边坡数值模型细观参数,监测数值边坡模型关键位置的速度、位移和孔隙率,结合边坡内部的裂纹发育和力链分布情况,分析边坡的破坏过程特征。结果表明:基于离散元的数值模拟试验和边坡数值模型均符合实际情况,具有可行性;边坡的破坏过程是在剪切应力和拉应力作用下,顺倾节理处的力链由下至上逐渐断裂,随着断裂范围扩大,边坡发生加速滑动,具体表现为受顺倾节理控制的前缘牵引式剪切-张拉组合破坏;节理上部的“拱形”力链未被破坏,滑坡特征为沿节理面和岩桥的整体滑动。

In order to analyze the inclination joints failure process of rock slope,a slope of an open-pit mine was taken as an example. The numerical model of a typical profile was developed. The mesoscopic parameters of slope numerical model were calibrated by laboratory tests. The velocity,displacement,porosity,internal crack development and force chain distribution at key positions of numerical slope model are analyzed,and the failure process characteristics of slope are obtained. The results show that The numerical simulation test and slope numerical model based on discrete element method are feasible and accord with the actual situation. The failure process of the slope is as follows. Under the action of shear stress and tensile stress,the force chain at the inclined joint gradually breaks from bottom to top. With the expansion of the failure range,the slope accelerates sliding,which is characterized by the front traction shear-tension combination failure controlled by the inclination joint. The “arch”force chain at the upper part of the joint is not destroyed,and the landslide is characterized by integral sliding along the joint plane and rock bridge.