Reinforced Soil Slope Optimization Design Method Research Based On Sensitivity Analysis

Reinforced soil slope is a new type of retaining wall which is introduced of ribbonin the soil. Reinforced soil slope improved the performance of the soil by the frictionbetween the ribbon and the soil. The nature of reinforced soil slope is outstanding.Thespecial structure of geogrid with vertical and horizontal connections can avoid localsubsidence of packing, minimize the uneven settlement of soil, enhance the overallstability of the soil. In recent years, reinforced slope has been widely used and promotedalong with the development of reinforced soil technology. But its design theory isrelatively backward compare with its engineering practice. So in this background,thisarticle studies the following several aspects:1．The finite element model is established through the international general finitesoftware PLAXIS, the experimental model of the same size with the finite elementmodel is established in the laboratory. Found that,slope failure surface location get fromthe finite element strength subtraction simulation is close to the experimental failuresurface position through the comparion for the finite element calculation results and theexperimental results. Thus proves that the finite element strength subtraction results areaccurate and available.2．By keeping other slope parameters constant and a single parameter changing,different finite models are established with the different similar frictional coefficient,different cohesion force, different gravity of soil, different friction angle of soil,different vertical interval of ribbon, different stiffness of ribbon and different length ofribbon. Get safety factor and failure surface position under different working conditionsthrough finite element strength subtraction. And then get the change rule for the safetyfactor and failure surface position of the reinforced soil structure along with thechanging of each influence factor.3．By means of grey correlation theory, select the change values of all influencefactor as the comparison matrix and select the corresponding safety factor as referencematrix.Then do the sensitivity analysis of the influence factor. Thus getting thesensitivity of each influence factor.(Among them, the internal friction angle of soil hasthe strongest sensitivity, the severe of soil has the weakest sensitivity.)4．On the basis of sensitivity ananlysis, through the method that,firstly determinethe design parameter which has the strongest sensitivity among all the influence factorof the reinforced soil slope stability,then determine other design parameter which hasthe weaker sensitivity in turn, get the optimum design method of reinforced slope basedon the sensitivity.5．At the end of the paper,use a high slope at the airport as an engineering example.Propose a scenario for the slope through the optimization design method proposed inthis paper.Then compare the optimizing project with the original plan. The resultsshowed that,when the safe factor is close,the desigh method proposed in this paper canwidely reduce the amount of ribbon and reduce the cost of the slope.Thus verifying thefeasibility of disigh method proposed in this paper.