Stability of Huangtupo Riverside Slumping Mass Ⅱ# under Water Level Fluctuation of Three Gorges Reservoir  

作　　者：胡新丽 唐辉明 李长冬 孙仁先 

机构地区：[1]Faculty of Engineering,China University of Geosciences [2]Hubei Center of Geological Hazard Control

出　　处：《Journal of Earth Science》2012年第3期326-334,共9页地球科学学刊（英文版）

基　　金：supported by the National Natural Science Fundation of China (No. 40872175);the National Basic Research Program of China (973 Program) (No. 2011CB710604)

摘　　要：After the normal operation of the Three Gorges Reservoir,the water level of the reser-voir will fluctuate periodically.Water level fluctuation will soften the rock and soil on the banks,induce underground water fluctuation and decrease the shear strength of rock soil on the banks,and in turn affect the landslide stability.The Huangtupo（黄土坡） landslide is a typical large and complex landslide in the Three Gorges Reservoir region.In particular,the stability of its riverside slumping mass has a great stake.On the basis of the analysis of engineering geological condition and formation mechanism of the Huangtupo landslide,the authors established the 2D finite element model of riverside slumping mass II# and selected proper mechanical parameters of the rock.With the GeoStudio software,ac-cording to the reservoir running curve,the simulation on coupling effect of seepage field and stress field was conducted in 7 different modes in a year.The results showed that：① Huangtupo landslide is a large and complex landslide composed of multiple slumping masses,which occurred at different phases.Before reservoir impoundment,it was stable;② it is quite difficult for riverside slumping mass I# and II# to slide as a whole;③ the stability coefficient of riverside slumping mass II# changes with the res-ervoir water level fluctuations.The minimum stability coefficient occurs 48 days after the water level starts to fall and the moment when the water level falls by 11.9 m.Landslide monitoring result is con-sistent with the numerical simulation result,which shows that although the reservoir water level fluc-tuation will affect the foreside stability of the landslide and induce gradual damage,the riverside slumping mass II# is stable as a whole.After the normal operation of the Three Gorges Reservoir,the water level of the reser-voir will fluctuate periodically.Water level fluctuation will soften the rock and soil on the banks,induce underground water fluctuation and decrease the shear strength of rock soil on the banks,and in turn affect the landslide stability.The Huangtupo（黄土坡） landslide is a typical large and complex landslide in the Three Gorges Reservoir region.In particular,the stability of its riverside slumping mass has a great stake.On the basis of the analysis of engineering geological condition and formation mechanism of the Huangtupo landslide,the authors established the 2D finite element model of riverside slumping mass II# and selected proper mechanical parameters of the rock.With the GeoStudio software,ac-cording to the reservoir running curve,the simulation on coupling effect of seepage field and stress field was conducted in 7 different modes in a year.The results showed that：① Huangtupo landslide is a large and complex landslide composed of multiple slumping masses,which occurred at different phases.Before reservoir impoundment,it was stable;② it is quite difficult for riverside slumping mass I# and II# to slide as a whole;③ the stability coefficient of riverside slumping mass II# changes with the res-ervoir water level fluctuations.The minimum stability coefficient occurs 48 days after the water level starts to fall and the moment when the water level falls by 11.9 m.Landslide monitoring result is con-sistent with the numerical simulation result,which shows that although the reservoir water level fluc-tuation will affect the foreside stability of the landslide and induce gradual damage,the riverside slumping mass II# is stable as a whole.

关 键 词：operating condition Three Gorges Reservoir riverside slumping mass Ⅱ# Huangtupolandslide finite element method landslide stability. 

分 类 号：TV221.2[水利工程—水工结构工程]