瑞利波作用下缓倾场地流滑大变形的SPH数值模拟  

Numerical simulation of Rayleigh wave-induced large lateral spreading deformation in gentle sloping ground using SPH

作　　者：李云屹 王睿[1] 张建民[1] LI Yunyi;WANG Rui;ZHANG Jianmin(State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学水利水电工程系水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《岩土工程学报》2023年第7期1333-1340,共8页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金优秀青年科学基金项目和面上项目(52022046,52038005);水沙科学与水利水电工程国家重点实验室项目(2021-KY-04)。

摘　　要：地震可能导致土体弱化甚至液化,从而在倾斜场地引起流滑变形,一般认为在缓倾场地中这种变形相对有限。然而,在2018年苏拉威西地震中,3°以内的缓倾场地却出现了数百米的大变形。已有的模型试验与数值计算大多只考虑了剪切波的作用,无法再现和解释这一现象。通过光滑粒子流体动力学法(Smoothed Particle Hydrodynamics,SPH)开展数值模拟,发现瑞利波对流滑大变形有显著影响。模拟使用HBP(Herschel Bulkley Papanastasiou)流变学模型模拟地基土,使用动力粒子边界(Dynamic Boundary Particles,DBP)实现瑞利波的非一致输入,结合地理信息系统(Geographic Information System,GIS)进行三维建模,计算并对比分析了瑞利波和剪切波输入下Balaroa缓倾场地的变形特征,解释了2018年苏拉威西地震Balaroa滑坡的成因。The sloping ground may suffer from lateral spreading due to earthquake-induced soil softening or liquefaction,and this deformation is usually relatively limited in the gentle sloping ground.However,several hundred meters of lateral deformation were observed in gentle sloping ground within 3°during the 2018 Sulawesi Earthquake.This phenomenon can not be explained through the observations from the existing model tests and numerical computations,where only the shear wave ground motion is considered.The numerical simulations using the smoothed Particle Hydrodynamics(SPH)method are conducted to show that Rayleigh wave input plays an important role in lateral spreading in the gentle sloping ground.The ground soil is simulated through the Herschel Bulkley Papanastasiou(HBP)rheology constitutive model,the Rayleigh wave is input using the dynamic boundary particles(DBP)boundary condition,and the geographic information system(GIS)is utilized for 3D spatial modeling.The deformation characteristics of the gentle sloping ground under the Rayleigh wave and shear wave are computed and compared,revealing the cause of the observed large deformation of Balaroa landslide in 2018 Sulawesi Earthquake.

关 键 词：瑞利波 光滑粒子流体动力学法 流滑 大变形 数值模拟 

分 类 号：TU435[建筑科学—岩土工程]