物质点强度折减法及其在边坡中的应用

Material point strength reduction method and its application to slope engineering

物质点法适用于模拟连续介质大变形,如边坡失稳全过程。在物质点法中应用强度折减法,用于边坡稳定性评价。与极限平衡法相比,二者安全系数计算值、滑动面位置结果基本一致;与有限元强度折减法相比,物质点法失稳评价标准的物理意义明确。利用物质点法大变形计算优势,评价边坡失稳后的破坏后果,通过算例说明其评价不同安全系数下的滑坡堆积形态及滑移距离的能力,尤其是评价滑坡对临近建筑物的影响程度的能力。物质点强度折减法可用于边坡稳定性评价及边坡破坏后果评价。

The material point method（MPM） is applicable to simulate large deformation of continuous medium, such as slope failure process. The strength reduction method（RSM） is applied to material point method for evaluating slope stability. In a slope stability evaluation example, the safety factor and slip surface position are got respectively by limit equilibrium method（LEM）, finite element strength reduction method（FEM-RSM） and material point strength reduction method（MPM-RSM）. Compared with LEM, the caculated results of safety factor value and slip surface position by MPM-RSM are basically the same with LEM and FEM-RSM. Compared with FEM-RSM, the physical meaning of MPM-RSM＇s failure evaluation criterion is more clear. Taking advantage of its superiority in calculating large deformation, MPM-RSM can evaluate the consequences after slope failure. A case study shows its performance in evaluating debris shape and sliding distance for different safety factors, especially the advantage in estimating the impact degree of landslide on adjacent buildings. MPM can be used for the evaluation of slope stability and evaluation of slope failure consequence.