Optimization Of Natural Frequency Of Box Shaking Table Based On Improved Genetic Algorithm

With the progress of science and technology and construction technology,the scale of construction projects is increasing,and there is a significant demand for structural optimization of large structures.For the optimization of large and super large structures,the design parameters are often very complex,and there are often a large number of discrete and continuous variables in the structural variables.It is difficult to establish an accurate mathematical model for that,instead,we need to simulate it with the help of finite element analysis software.The traditional optimization methods has limitations in dealing with the structural optimization problem with discrete variables,and the existing collaborative optimization methods has a low computational efficiency.Therefore,the research on how to accurately and quickly optimize the large-scale structure has scientific and practical significance.As an important part of shaking table test system,the geometric structure and the quality of the body have a direct impact on the performance and test accuracy of the system.In this paper,the optimization of structural discrete and continuous variables of box shaking table has been researched.The main task is collaborating the improved genetic algorithm with ANSYS software and the main contents of this paper are as follows:(1)The discrete variables(longitudinal plate distribution)and continuous variables(plate thickness,table height,etc.)of the box shaking table are parameterized,and the continuous variables of the table are optimized by using the optimization algorithm of ANSYS.(2)The problem that early convergence,poor accuracy,and the computational efficiency can be improved.The initial population generation scheme based on Hamming distance ratio and the improved genetic operator are introduced into the algorithm.With a large number of examples are made,the reasonable value range of various parameters of the improved genetic algorithm is given.(3)The traditional interaction mode between ANSYS and MATLAB is improved.By introducing the storage table and the internal loop strategy by ANSYS,number of calls to ANSYS during the iteration process is reduced,and the computation time is saved by 78%(4)Based on MATLAB platform,the collaborative optimization calculation of improved genetic algorithm and ANSYS software is realized,The results show that the first order natural frequency of the shaking table optimized by the improved genetic algorithm is 12.1Hz higher than the original design value,6.2hz higher than the result of zero order optimization and 0.5Hz higher than the result of first-order optimization.(5)The structural optimization analysis of 16m×20m shaking table body shows that the quality of the optimized generalized model is reduced by 2 tons and the frequency is increased by 1.73 Hz compared with the original designed generalized model.The results show that the first order frequenciy of the shaking table optimized by the improved genetic algorithm are better than the original design model.