Wujiayuanzi Landslide Stability Analysis Of Different Sections In Conditions Of Water Level Fluctuation And Rainstorm

Wujiayuanzi(WJYZ)landslide is located in the right bank of Shennong River in the town of Yanduhe in Badong County,The right side of landslide had partial sliding motion which is Yaojiatan(YJT)in 2009.There are no obvious signs of deformation on the left side,the middle section and the right side of the lot.Due to the inherent control of topography,slope structure and material composition and other factors diffenent,landslide stability of different sections are also various.Based on the analysis of the dynamic characteristics of WJYZ landslide in different sections in the Three Gorges Reservoir area,using commercial software SEEP/W module and SLOPE/W module of GeoStudio2007,launched 24 water level fluctuations in conditions representative of different sectional seepage field simulation and landslide overall stability and local stability calculation.Calculated the stability coefficient of different sections of landslide with unbalanced thrust method by using Lizheng software and Compared with.Morgenstern-Price method results,prediction of the different sections of WJYZ landslides landslide stability and deformation trend with the fluctuations in water level and superimposed extreme storm conditions,Using the finite difference software FLAC3 D,.simulate landslide damage in different conditions of deformation features.Results are showed as follows:(1)WJYZ landslide is a typical rock landslides,There is no large-scale landslide overall signs of deformation,however,fluctuating water level segment with sporadic occurrence bank collapse,Landslide in the middle professional monitoring data reflected a weak surface modification,local damage occurred on the right of the slope YJT section of the landslide,but the monitoring point displacement law is not obvious,displacement rate is larger from May to September in every year,the other time is relatively small.Reflecting the slope surface stability of the landslide affected by rainfall and reservoir water level.Under the current conditions,the landslide is stable,and the YJT section on the right of the landslide is basically stable,and the local stability of the front is poor.(2)Under the condition of reservoir water level decline,the water level in the slope is decreased,and the water level in the slope is lower than that of the reservoir.The stability coefficient of landslide is decreased,and the rate of reservoir water level decline is greater,the water level in the slope is lower than that of reservoir water level.The slope stability factor decreased faster,the lower the minimum stability coefficient.Different sections of WJYZ landslide under the same conditions,the stability coefficient of landslide on the left side of the WJYZ landslide is the largest,and the stability coefficient of the YJT landslide is the least.(3)Under the condition of reservoir water level rising,the rise of water level in the slope is lagging behind the rising of reservoir water level,and the stability coefficient of the landslide is increased.The rising rate of reservoir water level is higher,and the water level in the slope is higher than that of reservoir water level.The stability coefficient of WJYZ landslide increases faster,and the maximum value of stability coefficient is higher.Different sections of WJYZ landslide at the same rate of rise,the stability coefficient of WJYZ landslide on the right side of the landslide is the smallest,while the YJT landslide is the largest.(4)The water level steady state superposition of different storm conditions,the WJYZ landslide in different sections of the stability coefficient is decreased firstly and then increased,As time continues to rise and tends to be constant after the minimum value is reached.Under the same rainfall conditions,the stability coefficient of the YJT landslide is the smallest.In different places of WJYZ landslide,The YJT landslide is influenced by heavy rain.(5)FLAC3D's simulation results show that the deformation of the middle area of WJYZ landslide and YJT landslide mainly appears in the middle of the sliding body and the margin,The maximum displacement occurs on the YJT landslide,the surface displacement is greater than the displacement of deep.With the decrease of landslide stability,the shear strain increment range extends to the front and back of the sliding body,The value and range of deformation and shear strain increment in the middle of the sliding body are larger,and the plastic zone expands outwards,but no through plastic zone,the whole and local landslide will not be lost.