Study On Regional Slope Stability Based On Numerical Simulation Of Rising Groundwater Level

Xi'an Bailu plateau is a typical loess plateau landform.Affected by geological structure and climate evolution,the geological hazards of its landslides are widely developed,which causes huge economic losses to local residents.In order to study the development law of geological disasters in Bailu plateau landslide,the regional slopes in the study area were evaluated for stability under the influence of groundwater,and then guide people to scientifically prevent and reduce disasters.This paper takes Bailu plateau as a research object30km southeast of Xi'an City,through the collection of data,field geological survey,indoor experiments,numerical simulation and other technical means to reveal the distribution law,genetic type and development characteristics of Bailu plateau regional landslide geological disaster Basic information about geological disasters.Using the Seep/w module in the Geostudio numerical simulation software to study the changes of the groundwater seepage field in Bailu plateau,combined with the Slope module,the changing law of the stability coefficient of the slope model under different water heads was analyzed.Based on the above foundation,the Scoops3D three-dimensional deterministic model is used to simulate the change of regional slope stability factors of Bailu Plateau under the current situation and the rise of groundwater level.The main conclusions drawn by the study are the following:(1)According to statistics,Bailu plateau has 74 landslide geological disasters,which are distributed along the banks of Ba River and Chan River in strips.According to the type of development,there are mainly landslides in the loess layer,loess-paleo-soil landslide,loess-red clay landslide,loess-bedrock contact landslide.According to the cause type,it can be divided into five types:rainfall-induced type,reservoir storage-induced type,human engineering activity-induced type,river erosion-induced type,and groundwater level rise-induced type.The characteristics of landslide development are mainly the local revival of the old landslide.(2)Using the Geostudio software to numerically simulate the loess+red clay slope model.It can be seen from the simulation results:under the conditions of setting 80m,85m,90m,95m,and 100m,with the rise of the groundwater level,the area of the saturated area in the model body gradually increases,the area of the unsaturated area gradually decreases,and part of the unsaturated area begins conversion to saturation.Correspondingly,the slope stability coefficient decreased from 1.110 at the head of 80m to 1.041 at the head of 100m until the head was applied to 115m,and the entire slope model reached the limit equilibrium state.(3)The Scoops3D three-dimensional deterministic model was used to study the regional slopes of Bailu plateau.From the research results,it can be seen that under the current conditions,the distribution area of the unstable area of Bailu Plateau is 0.The distribution area of the less stable area is 1.26km~2,mainly distributed in Yeshi-Baimiao Section,Jingyugou Section,Sanyangpo-Majiashizi section and Yangliupo section.The distribution area of the stable area is 12.66km~2.The distribution area of the extremely stable area is 250.18km~2(4)Under the current conditions,the regional slope of Bailu plateau has better self-stability.As the groundwater level rises by 5m,10m,15m,20m,and 35m,the slope stability coefficient begins to decrease.The extremely stable area gradually transforms to the stable area,the stable area gradually transforms to the unstable area,and the less stable area gradually transforms to the unstable area.The conversion degree of Sanyangpo-Majiashizi and Yangliupo section is the most obvious,which shows that the area is more sensitive to groundwater response.