尼续高速远程滑坡形成机制及运动过程模拟研究OA

Based on the Nixu rapid and long-runout landslide in Nixu Village,Xumai Township,Nimu County,Lhasa City,Tibet Autonomous Region,the formation mechanism was preliminarily determined by detailed geologi-cal survey.The motion process of the Nixu landslide was simulated by the 3D calculation model based on the finite difference method.The results show that the unstable block disintegrated in the transportation zone after seismic triggering,and the broken block was impacted to breakup in the circulation area to wrap the coarse sand before the slope to move on.After reaching the valley terrace,the liquefaction caused by the loading and shearing of the over-lying saturated sand layer by the sliding body is the main formation mechanism of the Nixu rapid and long-runout landslide;The duration is approximately 215 seconds with a maximum average speed of 34 m/s.The overall speed shows a trend of"sharp acceleration-continuous deceleration".The simulated slip distance,velocity,accumulation range and thickness align well with field survey results,confirming that high liquefaction significantly promotes landslide movement.This conclusion can provide reference for studying high-speed and long-distance landslide movement in similar areas.