Stability Analysis And Reinforcement Measures Of A High Slope Along Highway 216 In Sichuan Province

The high gravel cutting slope of Section K46+100～K46+160 of Highway 216 in Sichuan Province is located in Muli County,Liangshan Prefecture,Sichuan Province.After the slope was excavated,only simple reinforcement measures had been taken.Under the action of long-term rainfall and earthquake waves,the shallow surface of the slope slips,which brings great hidden dangers to people’s lives and road traffic safety.Therefore,it is necessary to evaluate the stability of the slope and put forward a reasonable treatment scheme for the slope according to the actual situation.Through on-site investigation and research,this paper consults the relevant geological survey data,and classifies the slope according to the previous research results.By using the method of theoretical analysis and numerical simulation,the slope stability was studied deeply,and the stress distribution of rock and soil in the slope before and after treatment and the distribution of slope displacement and shear strain increment under different working conditions were analyzed.The advantages of anchored SNS net compared with traditional prestressed anchor cable in strengthening slope were compared and analyzed from many aspects.The dynamic response characteristics of slope under earthquake were studied deeply.The main contents and results are as follows:（1）The stability of the slope is calculated by the transfer coefficient method,and the results show that the slope is unstable under multiple working conditions.The residual sliding force of the slope under the most unfavorable working conditions is calculated.on this basis,the treatment scheme is selected,and the anchor pier active protection net is designed through theoretical calculation.（2）The slope before treatment is simulated by FLAC^3D finite difference software,and the results show that the stability factor obtained by transfer coefficient method is similar to that obtained by strength reduction method.The result calculated by the transfer coefficient method is unsafe.Therefore,the factor of safety calculated by the strength reduction method is reliable.（3）The displacement,shear strain increment and maximum and minimum stress distribution of the slope before and after treatment are studied by FLAC^3D software.It is found that the new type of anchored SNS net has obvious advantages in controlling the slope displacement compared with the traditional prestressed anchorage cable reinforced slope.（4）After setting the boundary conditions and inputting seismic waves in the established numerical model,it is found that the slope can amplify the peak acceleration in both horizontal and vertical directions.Under the action of different duration of seismic waves,the peak acceleration amplification coefficient of the slope and the slope does not change much.After using the anchored SNS net to control the slope,the peak acceleration magnification factor of the slope in the study area changes greatly,while the peak acceleration magnification factor of the slope body changes little,which is due to the high strength of the bedrock itself.This paper is the stability analysis and treatment of the actual slope engineering.The reinforcement measures and relevant conclusions adopted in this paper have a certain reference value for similar slope reinforcement projects.