Shallow Landslide Stability Study Based On Water Content Change

with the increase of human engineering geological activities,landslide disasters are becoming more and more serious.The research results of the side slope of an entire highway in Xiangxi manifested that landslide geological disasters are very serious,the type of disasters are all shallow failure,the “resurrection” of disasters is obvious in the section which has a large variation of water content in the shallow soil sample.To achieve the safety precaution and efficient management of the side slope during their service period.The thesis takes the cutting high slope of a highway K86+700~K87+130 in Xiangxi as research object,using the methods of field investigation,laboratory experiment and theoretical analysis to study the pattern of slope safety factor change with its water content.Specific content as follows:(1)The study of the spatial distributive characteristics of the water content in shallow soil of the slope.Using field investigation and sampling,laboratory experiment and analysis to study the pattern of the variation range and space of water content in first slope 1:0.75,second slope 1:1 and third slope 1:1.2 separately.(2)The study of the impact water content have on the shear strength of shallow soil of the slope.By launching the consolidated-undrained quick shear test of soil sample with different water content,and using fitting analysis,achieved the function relationship of water content,the cohesive and the internal friction angle.(3)The research of the pattern of slope safety factor change with water content.Using the software GEO-Slope to analyze the stability of slope,by changing its water content to study the pattern of slope safety factor change with water content.It was simplified as a chart,for engineering reference.Main conclusions are as follows:(1)The variation range of water content in shallow soil of these three slopes are upslope 18.98%~24.35%,midslope 20.46%~25.16% and downslope 20.73%~26.33%,in the same profile,the water content in downslope,midslope and upslope increase successively.(2)The relation of the water content in the shallow soil of the slope,the cohesive and the internal friction angle is a semilog linear relationship.(3)On the basis of water content change in the control point in the top of slope,we obtained the water content threshold of the slope in safe state,unstable state and a possible landslide disaster state.(4)The simplified chart of the safety factor of the shallow soil of the slope can provide reference for the slope's early warning and safety management.