An Optimization Design Method Of Anchor Reinforcement Location Of Soil Slope And Ts Application

With the development of land resources and the growth of the global population,the slope issue has become a global geological hazard with earthquakes and volcanoes.Therefore,it is particularly important for the reinforcement of engineering slopes.Among the technical measures used in the reinforcement of engineering slopes,prestressed anchor cables have been widely used in practical projects because of their unique characteristics.In recent decades,many scholars have studied the prestressed anchorage technology and further optimized the prestressed anchorage technology.For the optimization of prestressed anchor cables,some scholars have put forward the general principle of the overall arrangement of prestressed anchor cables by emphasizing “strong waist and foot stability” to avoid “top-heavy” and “preventing top-down” phenomena through research and practice..However,the research on the optimal layout design method of prestressed anchor cables is still not enough,resulting in the random arrangement of prestressed anchor cables,and the reinforcement effect of anchor cables on the slope is not optimal.This paper aims at the optimization of the prestressed anchorage reinforcement for engineering slopes,and reinforces the first-order and multi-level homogeneous soil slopes based on single-row and multi-row anchors.Analysis of the effect of different layout methods of anchor cables on the safety factor of slope reinforced by prestressed anchor cables,and analysis of the influence of different slope angles,different soil mechanics parameters combinations,different anchor cable inclination angles and anchor cable prestressing forces on the optimal arrangement position of the anchor cables,systematic summary of the principles of optimal placement of prestressed anchor cables for reinforced slopes,and the optimization design method of prestressed anchor cables for reinforcement of slopes.The main research contents and conclusions of the paper are as follows:(1)The slope safety factor is analyzed by using the limit equilibrium method to reinforce the first-order and multi-level soil slope models at different positions in a single row of anchor cables,and by comparing the size of safety factors,summarize the general rule of optimal placement of the slope reinforced with single row anchor cables.On this basis,the influence of the optimal installation position of the anchor cable when the basic parameters of the primary and multi-grade soil slopes are changed is analyzed.The results show that the optimal position of anchored cable slope is generally in the lower part of the slope,and with the reduction of the position of the anchor cable in the slope,the overall stability of the slope is gradually improved and the local stability is gradually reduced.When the angle of slope increases,the height of the optimal laying position of the anchor cable increases;the height of the optimal laying position of the anchor cable decreases with the increase of the cohesion c and internal friction angle ? of the slope soil;the increase of the dip angle of the anchor cable reduces the height of the optimal arrangement position of the anchor cable;the change of the prestressing force of the anchor cable has little effect on the optimal position of the anchor cable.(2)Using the method of limit equilibrium to analyze the slope safety factors of first-level and multi-level soil slope models with different arrangements of prestressed anchor cables at different positions,and by comparing the size of safety factors,summarize the general laws of optimal layout of multi-row prestressed anchor cables for reinforcing soil slopes.The results show that the optimal arrangement position of the multi-row anchor cable reinforcement and multi-row anchor cable reinforcement of the first grade slope of the same slope is the position from the lower part of the slope to the foot of the slope,with the reduction of the anchor laying position,the overall stable safety factor of the slope is gradually increased and then decreased;the partially stable safety factor gradually decreases.With the increase of the number of slopes,the ? value of the optimal reinforcement position of the multi-row anchor cable reinforced soil slope is reduced.(3)By comparing the calculation results of the one-level and multi-level soil slopes reinforced by single row and multiple row anchors,it can be seen that the optimal arrangement position of the reinforced slopes with anchor cables is basically the same,based on this,an optimized design method for slope reinforcement with prestressed anchor cables is proposed,that is,when multi-row anchor cables are used to reinforce the engineering slope,it is possible to first search and calculate the optimal arrangement position when the single-row anchor cable is used to reinforce the slope,and then center on the optimal arrangement position of the single-row anchor cables,symmetrically symmetrical anchor cables with the remaining total anchor cable prestressed are arranged equally on both sides of the central anchor cable,and the prestress of a single anchor cable placed at the position of the central anchor cable near the foot of the slope can be appropriately increased.At the same time,in order to prevent local damage,the minimum slope installation height search can be performed through the minimum requirements for the safety factor after reinforcement of the slope,so as to achieve the optimal layout of the multi-row anchor cable reinforcement slope.(4)Using the calculation method of this paper,the slope in the actual project is simulated and calculated.The safety factor of the slope before and after reinforcement is basically consistent with that in the literature.And the actual engineering case is optimized by the optimization method proposed in this paper.The safety factor obtained is slightly larger than the safety factor of the reinforced slope of the anchor cable in the literature,that is,it is safer than the arrangement method of the anchor cable in the literature.Therefore,the optimization design methods and steps proposed in this paper are effective and scientific.