Genetic Algorithm Optimization of Space Frame

Abstract

Structural design of space frames requires appropriate form for a structure so that it can carry the imposed loads safely and economically. Traditional approaches towards the task of finding such forms for structures have been by the use of experimental models or by intuition and experience. The main objective of this paper is to develop and use reliable, creative and efficient computational tools for the linearly elastic analysis and optimum design of space frame structures under static loads. The use of SAP2000 can assist greatly in achieving a safe design. However, commercially available programs are not designed as optimization tools. In this study for optimization of multistory structures, home written MATLAB code interface program is designed to connect SAP2000 which is known as a commercial nonlinear finite element program and genetic algorithm optimization program. The design algorithm obtains minimum weight frames by selecting suitable sections from specified group list, with consideration actual design constraints like, strength, lateral displacement, inter story drift according to Load and Resistance Factor Design (LRFD). The improved method is tested on different two dimensional multi story moment resisting frames. It is concluded that this method can be used as a useful tool in engineering design and optimization.