Optimal Design Of Gravity Dam Profile Based On ANYSYS And Genetic Algorithm

The gravity dam which include overflow section and non overflow section is a common type of dam,its functions mainly include hydration and drain water.In practical,the gravity dam has problems include too much big section size,too much needs of concrete and the foundation of large contact area,which make the bottom surface suffer too much uplift pressure that is not conducive to the stability of the dam other issues.These problems influence the quantity of the whole engineering and engineering investment,so optimize the design of gravity dam section is really necessary.Optimize design of the profile of gravity dam has great practical value to reduce the quantity of the whole project effectively and reduce investment.In this paper,the first order optimization method of genetic algorithm and ANSYS are used to optimize and analyze the overflow and non overflow dam section of a typical dam,the minimum profile are is set as objective function.Contents and results are as following:(1)The overflow section and non overflow section are optimized by ANSYS first order optimization method first.Use maximum water level's condition to check the profile is reasonable or not.The finite element model of spillway and non overflow dam section are established by using APDL language,the restrictions are imposed on boundary conditions of the finite element model and this model is calculated;The anti sliding stability coefficient,first principal stress,third principal stress and section area are selected to do optimization and analysis in process of post processing.The stress and displacement plots of two sections are checked to judge whether they meet the optimal design requirement;the results of the optimized method : the area of overflow section reduced 86.62m2,optimization rate reached14.43%;The area of non overflow section reduced 75.27m2,optimizing rate of 12.34%.The dam's optimal profile is proved in the condition of maximum water level that reach the requirement mentioned in design standards.(2)The genetic algorithm is used to optimize the overflow section and non overflow section.The initial population is generated according to the geometric constraints,the initial population is chosen as design variables;put the initial population into ANSYS analysis file,MATLAB is used to invoke the ANSYS file and calculate the state variables and objectivefunction values.Optimization is terminated when the number of iterations achieve the required iterations,otherwise the initial population will be chosen,crossover and mutation to form the new population,MATLAB will continues to call the new ANSYS file of new population to recalculate.The results of optimizations using genetic algorithm: the area of overflow section reduced 77.92 m2,optimization rate reached 12.80%;The area of non overflow section reduced 39.08 m2,optimizing rate of 6.05%.The dam's optimal profile is proved in the condition of maximum water level that reach the requirement mentioned in design standards.The optimization result in the bottomed width of overflow section and non overflow section of the dam is not same because the optimization is divided into two separate section to do optimization.So the bottomed width of the overflow section and non overflow section of the dam integrated optimization should be strictly control and this two sections should be put together to analyze in further study.