The Research And Application On Set Of Optimization Design Method Of High Arch Dam Based On The Finite Element Method

The key technique on the shape design of high arch dam is critical to dam safety and economy. The adaptability of arch dam to geology is more and more high, when the influence of complicated geology is considered, and the widespread used modern calculating methods in engineering, such as the finite element method(FEM), is considered during optimization design, the new challenge to old optimization design system of crown cantilever analysis is the full-automatic calculation problem of the different condition, different arch dam parameter, the possibility and the efficiency which were caused by the increments of calculation time. The set of optimization design method of high arch dam based on FEM was studied in the dissertation, according to the provisions of 《Design code of concrete arch dam》 which will soon be promulgated, and the optimization objective , project and method were put forward .The optimization design of arch dam and the related realm at present were concluded, the mathematics model and objective of optimization design in high arch dam were introduced in details, the conceived proposal and the key technique problem of set of optimization design method of high arch dam based on FEM were put forward.Under the computer parallel network environment, the modern optimization design method of nature evolution and the most optimum project, such as the Complex method, the Genetic Algorithms and the Evolution Strategies, etc were completed, and the multi-objective optimization was put forward by using "the gradual method"The general program to full-automatically generate meshes of different arch dam shape was completed, which considered the influence of plane fault, geologic region of various height , all horizontal fissure and process of concrete placement and reservoir storage, two kinds of projects were adopted to optimize the design of arch dam, One is to utilize the safety factor for stability of the abutment of arch dam and the stresses calculated by crown cantilever analysis as the constraints, at the same time, to use the concrete volume of arch dam as the objective, the other is to adopt the stresses computed by FEM and the depths of tensile stress as the constraints, the concrete volume of arch dam as the objective.The possible project was discussed based on nonlinear finite element method, the ratio of crack depth in upstream face of dam to thickness was utilized as the constraint according to design code, when the economic index was used as the objective, the safety scale of stability was used as objective function calculated by strength reduction coefficient, and the ratio of crack depth in upstream face of dam to thickness was used as constraint computed by nonlinear finite element method, when the safety index was adopted as optimization objective.By dynamic stability analysis and calculation in means of FEM, the three-dimension data processing technique for arbitrary cross sections of solid masses was adopted, then the safety factor of the abutment of arch dam was provided using FEM, and corresponding programs was compiled.