Study On Stability Analysis And Support Preference Of A Highway Slope In Zhejiang

The research on slope and supports is now developing in the direction of refinement,economy and environmental friendliness,however,most of the slope support research at the present stage only revolves around one type of support type,the detailed comparative research between different slope supports is less,and the slope support has not yet established a unified and systematic support preference evaluation system.Based on this,this paper proposes a slope support preference system,and takes a highway slope in Zhejiang Province as the research object to study the slope stability and slope support preference,which through numerical simulation,theoretical analysis,field monitoring and other methods.The main results are as follows:(1)The slope in the study area is mainly affected by rainfall and the development degree of rock joints,and the combination of rock mass structural plane and free surface is unstable.The adverse geology actions of the slope is mainly appears in the form of falling blocks and small-scale collapse,which seriously threatens the traffic safety,so the slope urgently needs support treatment.(2)The slope support simulation results are as follows:The safety factors of slopes under ecological slope protection,gravity retaining wall,soil nail+anti-slip pile and anchor+anti-slip pile support are 1.095,1.462,1.323 and 1.394,respectively.The slope supported by ecological slope is in the basic stable state,and the slope supported by gravity retaining wall,soil nail+anti-slip pile and anchor rod+anti-slip pile is in the stable state.Among the above four types of slope support,gravity retaining wall has the best support effect,followed by anchor+anti-slip pile,and the ecological slope has the worst support effect.(3)The evaluation system of slope support is constructed,and the slope support is comprehensively compared from four aspects of effect,construction factor,environmental factor and economic cost,the results of the comparison are as follows:The function coefficients of ecological slope protection,gravity retaining wall,soil nail+anti-slip pile and anchor+anti-slip pile support are calculated as 0.154,0.306,0.267 and 0.273,respectively;the value coefficients of support after combining with cost coefficients are calculated as 1.258,0.770,1.283 and 1.005,respectively.It can be seen that the value coefficient of soil nail+anti-slip pile support scheme is the biggest and its comprehensive cost-effective is the best.Combining with the numerical simulation results of the support,it can be seen that the support can meet the slope management needs,so it is recommended to choose soil nail+anti-slip pile support scheme for the slope in the study area.(4)The horizontal and vertical displacements of the slope supported by soil nailing+anti-slide piles are monitored,and the monitoring results are as follows:The slope displacement deformation began to stabilize after about 90 days,and the maximum accumulated horizontal displacement of the slope was 8.6 mm and the maximum accumulated settlement displacement was 3.2 mm after one year of monitoring.The slope monitoring results can provide practical data support for the slope support study.The displacement deformation of the slope supported by soil nail+anti-slip pile is small,and the slope under this support is in a stable state.The soil nail+anti-slip pile support scheme achieves the purpose of slope instability control.In this paper,the slope support preference system is used to determine the support scheme of the slope in the study area through numerical simulation and other methods,and this support scheme achieves the purpose of slope management,and this study can provide reference for similar slope support engineering research.