Study On Optimization Of Space Truss Based On Genetic Algorithm

Space truss is a form of spatial structure, which has more extensive use, such as gas station, stadium, theaters, large-scale restaurants, shopping malls and other places. The bars of space truss are arranged according to a certain regulation, and linked through nodes. Most of space truss is built of steel structure, so that it will be more valuable to study the optimization design of steel structures, thereby reducing cross-section and saving steel products. In this paper, the main method of optimization design is based on the genetic algorithm.The genetic algorithm is a burgeoning optimization algorithm, which belongs to bionics algorithm simulating biological evolution. Because of simplicity and high adaptability, the application of genetic algorithm to compute science and optimization design is given more attention, for example, function optimization, combination optimization, artificial intelligence, image manipulation, and so on. Based on reading a great deal of references and initiating widely investigation, the genetic algorithm and its application on structural optimization design are studied and summarized. The fundamental conceptions and main features are introduced here. Several key factors about genetic algorithm applied on structural optimization design are analyzed and studied, for example, the mathematical model and its constrained problem, the generation of initial stocks, controls parameter of genetic algorithm, and so on.In consideration of the characteristic of structural optimization and finite element theory, Matlab program is developed for analyzing plane truss and space truss, and calculating internal force and displacement of structure under dead load. Then the program acts as subprogram when the program of structure optimization based on genetic algorithm is developed for optimizing the element cross section of plane truss and the structure of space truss. Structure optimization of space truss consists of cross section area optimization of structural element and structural height optimization. Several design examples prove that the program developed for structure optimization is feasible and effective.