Lightweight Optimization Design Of Bridge Crane Girder Based On Memetic Algorithm

The method of traditional optimization design for the crane may easily lead to low efficiency, poor effect of weight loss and other issues. To solve those problems, the way of lightweight design combined with modern design method and intelligent algorithms is of great significance, which is mainly used in the key members of the crane. This paper focuses on analyzing the characteristics of lightweight design of the box girder which is the multi-dimensional and multi-constrained in the size optimization process, and puts forward the optimization design based on Memetic Algorithms. The main content include four points as follows:Firstly it introduces the research status of crane lightweight design and Memetic Algorithm framework, and makes sure the framework of constructing Memetic Algorithm to solve the problem of lightweight for crane box girder is determined.Secondly by studying the structure of the box girder and the stress on various conditions, the mathematical model using optimization method has been established. It includes the design variables, the objective function and others which is strength, stiffness, stability, boundary dimensions and so on.Thirdly by studying the key elements of the Memetic Algorithm framework, it will reintegrate the improved real-coded genetic algorithm and simulated annealing algorithm, and adds the strategy of ratio search comprehensively to form the framework of Accelerated Memetic Algorithm(AMA). Through the application of Accelerated Memetic Algorithm to resolve the same problem and then compare with existed literature, the results show that the Accelerated Memetic Algorithm has obvious advantages on optimization results and algorithms performance.Finally setting a certain type of crane box girders actually produced by a company to be the research objective, the control parameters of algorithm is determined by trial, and the design parameters of box girders cross-sectional dimension is solved. The results show that the solution of the optimization algorithm decreased sectional area of the crane box girder 17.38% than the existed crane box girder. Finally, the feasibility and rationality of the optimization results is verified through ANSYS Workbench finite element simulation.