Numerical Simulation Of The Technology Of Intercepting And Draining Water With Compressed Air For Landslide

Landslide is a common geological disaster with many characteristics,such as various forming conditions,complex influencing factors and huge damage loss.Statistical analysis shows that the uplift of groundwater caused by rainfall is the main trigger factor for the occurrence of landslides.Therefore,through the interception and drainage engineering measures,reducing the surface water and groundwater entering the potential landslide area to lower the groundwater level in the landslide is an effective measure for landslide control.At present,the most common drainage measures are the use of the gravity potential of water,but it is easy to fail due to clogging or cracking,or because of the expensive construction cost,such as underground drainage tunnels,are only used in large landslide.If we can find an economical and convenient way to break through the environmental constraints and reduce the groundwater level actively and quickly.It is of great significance to improve the stability of rainfall-induced landslides.This paper discusses a new method of water interception and drainage,that is,intercepting and draining water with compressed air method.It uses the characteristic of unsaturated soil that permeability decreases rapidly with the saturation decreasing.The rear edge of potential landslide area is artificially filled with gas,and the local unsaturated water curtain is formed by the principle of gas drive water,so as to reduce the supply of groundwater to the potential landslide area of the leading edge of the slope and lower the underground water level to improve the stability of the slope.On the basis of the existing study,the technology of intercepting and draining water with compressed air is studied in depth with the finite element numerical simulation in this paper,including influence factors,development of seepage and deformation of unsaturated zone and specific engineering case.The following three aspects are concretely included:(1)A two dimensional slope model is constructed by the finite element software.The influence of unsaturated soil layer thickness and inflating pressure on the effect of interception and drainage is explored.Besides,by monitoring the pore water pressure and seepage velocity at different locations of the slope after inflation,the influence of inflation on the seepage field in the slope is studied.(2)A non-complete coupled numerical simulation of seepage and deformation is conducted to simulate the formation process of unsaturated zone and the vertical displacement of soil on the slope surface when the water level is lowered by intercepting and draining water with compressed air.(3)Combined with the actual landslide cases,on the basis of the analysis of its deformation and failure characteristics and its formation mechanism,the numerical simulation method is used to demonstrate the effectiveness of the intercepting and draining water with compressed air technology in similar landslide treatment.