Optimization Design Of Bridge Crane Box Girder Based On Chaotic Genetic Algorithm

Bridge crane is widely used in various fields of national economy, the products havealready become general and series pattern. Bridge crane designed by traditional allowablestress method and limit state design method can satisfy the demand of practical engineering,but exist the problem of materials waste and greater weight. It has a positive meaning for thedevelopment of crane industry through seek out an optimized design, reasonable and effectivesolution to the above problems, improving design efficiency. Optimal design of thegirder structure in bridge crane has become more and more important.Because standard Genetic Algorithm exists some defects in solving engineeringoptimization problems. A new genetic algorithm based on Chaos has been proposed in thispaper. The Chaos theory and the dynamic genetic operator have been introduced to thismethod to solve the problems of traditional GA algorithm is easy to fall into local optimalsolution and has low iterative speed during later state. The main contents are followed:(1) According to the chaos in the characteristics of ergodicity and randomness usingchaotic sequence to improve the initial population generation in GA algorithm. The mostsuitable sequence can be selected by programming and simulation form large data sets.(2)The improvements of Genetic Algorithm genetic operators. To achieve the cr-ossover operation and chaos initialization phase matching using dynamic genetic operator.Convergence speeds has been improved and effectively reduce the probability of conv-ergence in local optimal solution.(3)Using this method to optimal design of crane girder. Establish the optimizationmodel of bridge crane girder. Compare with the genetic parameters through program anddetermine a set of parameters. Finally compare with the improved method and traditionalmethod through a index that is the speed of convergence, and verify the availability of newmethod through ANSYS finite element simulation. This paper provides a useful thought for improving the Genetic Algorithm optimizationof main girder of bridge crane, which has a certain reference value.