چكيده به لاتين
Nowadays, optimization is main interest of structural engineering in damage detection and structure optimization (e.g. size, shape or topology).size optimization is on the line for at least 2 decades, because of demand to lower project costs, prevent gas emition and finally improve design safety.
This study considers flat double layer grids which harnessed with steel cables. Sample example for our study is 520 member grid and is adapted from Prof. Kaveh and Dr Illchie, s book. The purpose of this research is to show the importance of modeling steel cables as harness to decrease inter-span deflection which leads to decrease in member’s tension, mutually cross section size and at the end total weight of grid.To do this, we have to recourse to the optimization methods.
Optimization methods are gradient based and metaheuristcs.gradient based or mathematical methods are older ways of optimization and have disadvantages like difficulty in implementing and understanding, getting trapped in local minima and pre mature convergence.to avoid these, metaheuristics developed from genetic (GA) & particle swarm optimization (PSO) algorithms from 90th.metahuristic method, oppositely do not have these problems and are based in physical interactions between species and other nature phenomena.
The present reasearch deals with optimization of double layer flat grid with steel cable harnesses. Space structures optimization is on focus of engineering duo to abundancy of members, design safety and economical purposes.in this study, four metaheuristic algorithms including CBO, ECBO, VPS and PSO, are applied to minimize structures total weight on the ground of cost function and well known penalty method employed to exert design constraints namely displacement, slenderness and stress ratio in optimization process. Results indicated that, by implementing steel cables as side sway impedance, structure’s weight diminishes approximately 30-40 percent as compared with simple structure.
