Dynamic process analysis of the Niumiangou landslide triggered by the Wenchuan earthquake using the finite difference method and a modified discontinuous deformation analysis

作     者：HUANG Da MENG Qiu-jie SONG Yi-xiang CUI Sheng-hua CEN Duo-feng HUANG Da;MENG Qiu-jie;SONG Yi-xiang;CUI Sheng-hua;CEN Duo-feng

作者机构：School of Civil and Transportation EngineeringHebei University of TechnologyTianjin 300401China State Key Laboratory of Geohazard Prevention and Geoenvironment ProtectionChengdu University of TechnologyChengdu 610059China 

出 版 物：《Journal of Mountain Science》 (山地科学学报（英文）)

年 卷 期：2021年第18卷第4期

页      面：1034-1048页

核心收录：

学科分类：081803[工学-地质工程] 0709[理学-地质学] 0819[工学-矿业工程] 08[工学] 0303[法学-社会学] 0818[工学-地质资源与地质工程] 0708[理学-地球物理学] 0705[理学-地理学] 0815[工学-水利工程] 0706[理学-大气科学] 0816[工学-测绘科学与技术] 0813[工学-建筑学] 0704[理学-天文学] 0833[工学-城乡规划学] 0713[理学-生态学] 0834[工学-风景园林学（可授工学、农学学位）] 

基　　金：supported by the National Natural Science Foundation of China(Nos.41672300 41902290) Opening fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology)(No.SKLGP2017K015)。 

主　　题：Wenchuan earthquake Discontinuous deformation analysis(DDA) Niumiangou landslide Amplification effects Displacement-dependent friction model 

摘      要：The Niumiangou landslide was the largest landslide triggered by the 2008 Wenchuan earthquake,which was significantly affected by the amplification effect of seismic acceleration.The ringshear experiments indicated that the materials in the source area of the Niumiangou landslide were subjected to friction degradation under a big shear displacement,which may result in rapid movement of the landslide.In order to better understand the landslide movement and study the effect of the friction degradation on movement mechanisms,the dynamic process of Niumiangou landslide was simulated with a new numerical method,which combines the finite difference method(FDM)and the discontinuous deformation analysis(DDA).First,the FDM was used to study the initiation time,amplification effect and velocity of the landslide.Afterwards,these initiation velocities were applied to the blocks in the DDA model by corresponding coordination in the FDM model.A displacementdependent friction model of the sliding surface was incorporated into DDA code to further understand the kinetic behavior of the landslide.The results show that the displacement-dependent friction strongly decreases the friction coefficient of sliding surface under a big displacement,which can obviously promote the run-out and velocity of landslide.The model output well matches the topographic map formed by the landslide.This implies that the proposed model can be applied to the simulation of earthquake-induced landslides with amplification effect,and the friction degradation model is important to clarify the movement mechanism of high-speed and long-distance landslides.