Study On Comprehensive Evaluation Of Slope Protection By Anchor Combined With Plant Root System

With the development of infrastructure construction in China,excavation and filling of ground rock and soil during engineering construction will destroy the original vegetation cover layer,cause secondary disasters such as landslides,and seriously endanger public safety.Therefore,how to carry out soil and water conservation and vegetation restoration on the premise of ensuring slope stability is the key problem in engineering construction in China.In this paper,based on a slope engineering in Dalian City,a slope supporting mode of bolt combined with plant root protection is established,and the slope stability and benefit evaluation of the slope protection mode are carried out,in order to provide technical support for engineering design.The main research contents and results are as follows:(1)The main failure modes of the slope are summarized and sorted out,and the main factors controlling the stability of the slope are screened.Through the analysis and study of the mechanism of bolt anchoring and shallow slope protection mechanism of plants,the combined support mode of bolt combined with plant root slope protection is proposed to reduce slope deformation and improve slope stability.(2)The finite difference software was used to simulate the deformation of a slope in Dalian under different working conditions.Based on the strength reduction method and the elastoplastic method,the horizontal deformation of the slope,soil settlement,penetration of the plastic zone and the safety factor were compared and analyzed.Then the stability of the ecological slope protection is evaluated according to the calculation results of slope deformation and safety factor under different slope operation conditions.The results showed that: Bolt joint has greatly increased the plant roots slope protection method of slope stability,safety factor of slope unstable state up to 1.777 from 1.189 the stability of the state,and through the analysis of the slope model before and after contrast to support that slope deformation occurred in the middle,can create biggest deal with its focus their support,support after the maximum deformation of slope to the slope toe,It has certain guiding significance to actual engineering.(3)The influence of various parameters on the slope stability of bolt-combined root support is studied.Through the analysis and identification of the influencing factors of slope stability,the variation law of slope safety factor under different parameters is simulated.The results show that the safety factor of the slope increases with the increase of the cohesion force and the internal friction Angle of the rock mass,and the cohesion force has a greater effect on the slope stability when the slope Angle is larger,while the internal friction Angle is opposite.The safety factor increases linearly with the increase of bolt length,plant main root length and planting layer density.When the bolt length exceeds the effective anchoring length,the slope stability will not continue to improve,and the slip surface will move to the slope surface and reduce the slope stability.(4)The slope benefit evaluation system of bolting combined with plant root protection was constructed.Firstly,the evaluation index system of slope benefit of bolt-combined root protection is screened and optimized.Then,the weight of each evaluation index is calculated by using the compatible matrix method and entropy weight method respectively,and the weight of evaluation index is optimized based on the relative entropy comprehensive weighting method.Finally,the slope benefit evaluation model based on the goodness evaluation method was established,and the benefit grade of the whole slope system with bolt combined root protection was determined to be the fourth grade with better benefit status.