Study On Stability Analysis And Anchorage Optimization Of High Rock Slope At Neixiang West Station

With the continuous development of society,railways and other transportation construction projects have also increased.As some railway projects have to be constructed in mountainous or hilly areas with complex terrain,tall and large cut rock slopes are often formed.The stability of these slopes It is related to the safety of the project,so it has always been a hot spot of people’s attention.The rock slopes near the Neixiang West Station of the Menghua Railway have high slopes,steep slopes,complex geological conditions,and most of them are bedding slopes,and the slopes are prone to instability and damage.This paper takes a certain rock slope near the construction site of Neixiang West Station in Nanyang City,Henan Province as the research object,uses limit equilibrium method,FLAC3D numerical simulation,and orthogonal experiment to analyze the deformation law of the rock slope.The safety factor of the slope was obtained,and the slope anchor rod was optimized by orthogonal test,and the optimal anchor combination was determined.The main research results are as follows:（1）Taking the study slope at Neixiang West Station as an example,combined with the engineering geological conditions of the area,it is concluded that the controlling factor of the rock slope instability is mainly the layer along the bedding,and through the stereographic projection method,the rock slope is analyzed.In an unstable state,it is prone to instability of plane sliding.（2）Using the limit equilibrium method to calculate,the safety factor of the rock slope under natural conditions is 1.402,which is greater than the limit value of 1.3 for the slope in a stable state specified in the code,and the slope is stable;considering the hydrostatic pressure of the top of the slope The safety factor of is 1.276,which is greater than 1.05,which is the limit value of the slope in a basic stable state stipulated by the code,and the slope is basically stable.At the same time,considering the hydrostatic pressure of the crack on the top of the slope and the floating force on the sliding surface,the safety factor of stability 0.812,which is less than the limit value of 1.00 that the slope is in an unstable state specified by the code,and the slope is unstable.The deformation characteristics of the rock slope under natural conditions are simulated by FLAC^3D,the overall displacement is small,the maximum vertical displacement value is 3.36cm,the stability safety factor is 1.207,and the slope is in a basically stable state.（3）Orthogonal test is used to optimize the design of the anchor parameters of the slope anchoring support.The inspection index is the slope stability safety factor.The variance analysis and range analysis simultaneously obtain the significance level of the anchor parameter factors that affect the slope safety factor.For the length of the anchor rod,the distance between the anchor rods and the distance between the anchor rods,the range analysis method shows that the influence of the anchor rod length on the safety factor of the slope is highly significant.Combining the two methods,the optimal anchoring combination is L_{4 2}D₃.Comparing the calculation of the L_{4 2}D₃ scheme with the original support scheme,the slope displacement and the maximum tensile and compressive stress on the slip surface are reduced to varying degrees,the safety factor is improved,and the optimization effect is significant.Finally,some opinions and suggestions on the shortcomings of provisions on seismic bearing capacity of foundation in seismic design codes is proposed.