Numerical investigation of friction-heating-pressurization and its control parameters in the shear band of high-speed landslides  

作　　者：ZHAO Nenghao CUI Shenghua LU Haijun 

机构地区：[1]School of Civil Engineering and Architecture,Wuhan Polytechnic University,Wuhan 430023,China [2]State Key Laboratory of Geo-Hazard Prevention and Geo-Environment Protection,Chengdu University of Technology,Chengdu 610059,China

出　　处：《Journal of Mountain Science》2024年第10期3380-3395,共16页山地科学学报（英文）

基　　金：financed by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(No.SKLGP2023K022);the Natural Science Foundation of Hubei Province(No.2022CFA011).

摘　　要：High-speed sliding often leads to catastrophic landslides,many of which,in the initial sliding phase before disintegration,experience a friction-induced thermal pressurization effect in the bottom shear band,accelerating the movement of the overlying sliding mass.To quantitatively investigate this complex multiphysical phenomenon,we established a set of equations that describe the variations in temperature and excess pore pressure within the shear band,as well as the conservation of momentum equation for the overlying sliding mass.With a simplified landslide model,we investigated the variations of temperature and excess pore pressure within the shear band and their impacts on the velocity of the overlying sliding mass.On this basis,we studied the impact of seven key parameters on the maximum temperature and excess pore pressure in the shear band,as well as the impact on the velocity of the overlying sliding mass.The simulation results of the standard model show that the temperature and excess pore pressure in the shear band are significantly higher than those in the adjacent areas,and reach the maximum values in the center.Within a few seconds after the start,the maximum excess pore pressure in the shear zone is close to the initial stress,and the shear strength loss rate exceeds 90%.The thermal pressurization mechanism significantly increases the velocity of the overlying sliding mass.The results of parameter sensitivity analysis show that the thermal expansion coefficient has the most significant impact on the temperature and excess pore pressure in the shear band,and the sliding surface dip angle has the most significant impact on the velocity of the overlying sliding mass.The results of this study are of great significance for clarifying the mechanism of thermal pressurization-induced high-speed sliding.

关 键 词：High-speed landslide Shear band Friction-heating-pressurization Numerical investigation 

分 类 号：P642.22[天文地球—工程地质学]