摘要
大型滑坡灾害往往带来巨大的人员伤亡和财产损失,开展滑坡灾害全过程数值模拟研究对滑坡风险定量评估具有重要意义。本文采用更新拉格朗日控制方程的物质点法,基于Drucker-Prager屈服准则下的理想弹塑性模型,考虑孔隙水压力效应推导等效内摩擦角,建立深圳“12·20”滑坡二维物质点法数值模型,再现了该滑坡失稳、运动和冲击过程。采用K均值聚类算法结合物质点的相对位移识别滑裂面,对滑坡运动过程中特征物质点速度变化进行分析,并参考泥石流冲击压力计算方法对滑坡运动物质的冲击压力和冲击荷载进行了初步计算。结果表明,物质点法模拟分析获得的深圳滑坡滑裂面形态、失稳和运动特征、冲击强度和堆积形态等与实际观察结果吻合较好,是再现滑坡稳定—失稳—运动—冲击—停积全生命周期的可靠数值模拟方法。
Large landslides often cause huge human casualties and property losses.It is of great significance to carry out numerical simulation of the entire process of landslide for quantitative landslide risk assessment.This paper establishes a two-dimensional material point method(MPM)numerical model for Shenzhen"12·20"landslide.This model incorporates the updated Lagrangian governing equation with the ideal elastoplastic model under the Drucker-Prager yield criterion.The equivalent internal friction angle is derived by considering the effect of pore water pressure.The K-means clustering algorithm is used to identify the potential slip surface in combination with the relative displacement of the material points.The computed results show that the landslide slip surface,instability and movement characteristics,impact strength,and deposition feature of the Shenzhen landslide obtained by the MPM simulation analysis are in good agreement with the actual observation results,which implies that MPM is a reliable numerical simulation tool to reproduce the entire life cycle of landslide stability,instability,movement,impact and deposition process.
作者
王升
曾鹏
李天斌
孙小平
WANG Sheng;ZENG Peng;LI Tianbin;SUN Xiaoping(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China)
出处
《工程地质学报》
CSCD
北大核心
2022年第4期1362-1370,共9页
Journal of Engineering Geology
基金
国家自然科学基金(资助号:41977224)
国家自然科学基金青年基金(资助号:41602304)
四川省科技计划(资助号:2019YJ0405).
关键词
物质点法
土质滑坡
滑面识别
运动过程
冲击压力
风险评估
Material point method
Soil landslide
Slip surface identification
Run-out process
Impact pressure
Risk assessment
