Mechanical Parameters’ Inversion Analysis Of Low Modulus Concrete Cut-off Wall Based On Adaptive GA

Low modulus concrete had been widely used in reinforcement engineering ofearth-rock dam, but there were disputes over the chose of experiment specimen’s sizeand the mechanics model in spite of Duncan–zhang model used by most persons. Inorder to validate the reasonable size and choose the mechanics model suited to lowmodulus of concrete, Mechanical parameters’ inversion analysis of concrete cut-offwall will be done based on the prototype experimental data of reinforced Bantou Damin NanAN. This article had researched for theory preparation to achieve that aim，including3-D stability seepage, program design of construction process of cut-offwall, program design of adaptive GA and tentative inversion analysis.Firstly, in order to coup with stress, equivalent node flow method was used tojudge the spill point, initial flow method was used to search the free face based on thefixed grids. Equivalent node flow method not only can satisfy the water headboundary, but also fulfill the flow boundary.Secondly, the elements lying in the cut-off wall was excavated by simulating as alevel of load to exert the other elements of the dam. The slurry wall stabilized wassimulated by elements with low modulus, poisson’s ratio of0.49, mud severe. Besides,the process of slurry wall stabilized and backfilled was simulated by replace ofelement properties. Element initial stress of storage period was the accumulation ofstress caused in slurry wall stabilized and backfilled.Thirdly, several methods such as niche algorithm, elite duplicate principles,best retain mechanism, combination between simple point cross and two points crossand adaptive improvement were used to improve simple GA. The improved effect ofInitial chromosome loci given zero was importantly tested. Then, based on thefunction test of non-adaptive and adaptive improvement, the influences taken by theinitial chromosome loci given zero and random generated had been tested. Throughthe comparison between the results of initial chromosome loci given zero and randomgenerated, Validity of initial chromosome loci given zero had been verified. Initialchromosome loci given zero to adaptive improvement can make the search accuracyimproved.Fourthly, the whole modulus was used in the analysis of the process of cut-off wall’s construction, the result of positive analysis can reflect the deformation andstress of concrete cut-off wall reinforced. Duncan-zhang E-B model, multi-potentialsurface model and Linear elastic model, were separately used as the mechanics modelof low modulus of concrete cut-off wall in the inversion analysis based on kept othermaterial parameters the same. Feasibility of the fitness function and effectiveness ofadaptive GA can be gotten.