【摘要】 针对某露天煤矿轮斗剥离台阶片帮情况,对剥离台阶岩土体进行了物理力学试验,基于有限差分方法,从边坡内部应力应变特征及塑性区扩展情况开展了单台阶片落体失稳机理分析,基于改进的结构面软化模型,采用连续—非连续单元方法(CDEM)对片落体滑塌及堆积的全过程进行了数值模拟分析,对片落体的运动轨迹及堆积情况进行了模拟分析,结合现场地质环境特征,分析了单台阶片帮的触发因素,结论表明,改进的结构面软化模型可作为地质体的渐进破坏的判据,真实还原片落体垮塌全过程;采用连续-非连续单元方法可模拟材料由连续体到非连续体的渐进破坏过程,实现大变形滑坡的灾变全过程分析,研究成果可为类似工况的边坡的评价及治理提供参考。更多还原

【Abstract】 A physico-mechanical test on stripping step rock and soil was carried out aiming at the stripping step spalling by wheel bucket in open-pit mine. Then,the instability mechanism of single step falling body was analyzed according to the stress-strain characteristics in slope and the expansion of plastic zone through a finite difference method. Based on an improved softening model of structural plane,the whole process of slip collapse and accumulation was simulated and analyzed by a continuous-discontinuous element method( CDEM). Moreover,the motion track and accumulation of the falling body were simulated and analyzed.Combining with the characteristics of geological environment in situ,the trigger factors of single step spalling were analyzed. The results show that the improved structural softening model can be used as acriterion of the progressive failure of the geological body,which can truly restore the whole collapse process of the falling body. The continuous-discontinuous element method can be used to simulate the progressive failure process of materials from continuum to discontinuity,and to realize the whole catastrophic process analysis of large deformation landslides. This study will provide reference for the evaluation and treatment of slopes under similar working conditions.更多还原