Analysis and Optimum Design of Curved Roof Structures

Abstract

Curved steel buildings are frequently designed to supply the users of the structure with ordinary light with a sense of capaciousness as well as grandness in public facilities such as stations, buying malls, leisure centres and airports. This paper presents a method for analysis and optimum design of 2D and 3D curved roof trusses subjected to static loading and specified set of constraints. Here the optimization refers to minimization of total weight of curved roof structures such that they can resist applied forces (stress constraint) and don’t exceed certain deformations (displacement constraints). The finite element formulations is developed and implemented for the static analysis of curved roof trusses to determine the stresses and displacements. The use of a reliable and competitive procedure for finding the optimum solutions for problems involving continuous design variables based on genetic algorithms is demonstrated and used in this study .The performance of genetic algorithms is affected by various factors such as coefficients and constants, genetic operators, parameters and some strategies. Member grouping and initial population strategies are also important factors. Optimization is an automated design procedure in which the computers are utilized to obtain the best results. The numerical methods of structural optimization with applications of computers automatically generate a near optimal design (converge to solve) in interactive manner. A program was modified and used to automate analysis and optimization of the structure written in FORTRAN language based Finite Element analysis and Genetic Algorithm optimization technique. The developed method is tested on several examples and compared with previous researches or SAP2000 results. It is concluded that this method can serve as a useful tool in engineering design and optimization of curved roofs.