Research On The Field Direct Shear Test And The Analysis Of Slope Control Of Sanming Shuiwu Banshanjun

Considering that the current research on the selection of in-situ soil parameters of landslide is relatively insufficient,which strongly influences the analysis of slope stability and deformation,this paper takes the excavation slopes in Sanming Shuiwu Banshanjun as example,following the research idea of "case analysis —— experimental research and controlling scheme recommendation —— numerical simulation prediction —— conclusion",traditional survey combined with field direct shear test method is applied to obtain the soil parameters of the slope accurately,and preliminary controlling schemes were put forward.Then numerical method was used to simulate the process of the field direct shear tests,and finally,the effect of the controlling schemes put forward was simulated and predicted by numerical method.The main contents and conclusions of the thesis are as follows:(1)The geological survey on the slopes in Sanming Shuiwu Banshanjun was carried on the survey and analysis,and combined with field direct shear test,the soil parameters of the slope is researched.The results indicate that the shearing resisting strength parameters of the granular intense-weathered quartz sandstone is c = 180.79 k Pa and phi = 35.33 °,and the shear strength parameters(friction)is c = 75.69 k Pa and phi = 35.23 °.Hence,referring to the engineering experience,the shear strength parameters after reduction is finally recommended as c = 40 k Pa,phi = 30 °.(2)The field direct shear tests were simulated by means of numerical method.The results show that the soil strength parameters obtained by numerical simulation are close to the measured values,and the accuracy of numerical calculation method is proved.Then the stress deformation characteristics of the sample were analyzed.Through numerical simulation,on the one hand,the direct shear test results that cannot be obtained in the field tests can be studied more comprehensively,on the other hand,the simulated results and the test results can confirm each other,and the feasibility and reliability of the numerical simulation can be validated by the measured data,which promotes the application of numerical method in the study of slope control.(3)Take the 3a-3a' section of ??slope as example,use anchor gridiron beam system as the control method,11 slope cases were simulated and the parameters in the sensitivity analysis are the number of the anchor gridiron beam system,the length of cable and the cable inclination.The results show that the final design of control scheme is: apply the anchor gridiron beam system to the first three excavation steps,and the cable inclination is 15°,the length of the second cables is 20 m,while the length of other cables is 10 m.Under such condtion,the lateral displacement can be reduced by 62.36% compared with the unreinforced slope.