Structural Weight Optimization of Frames Using Tabu Search. I: Optimization Procedure

A class of search techniques, heuristic search methods, and their suitability for structural optimization are considered for discrete optimization problems. The tabu search method is selected for application to structural weight optimization of skeleton structures. The search method is first tested to find the minima of a function in a nonlinear nonconvex optimization mathematical problem, and an algorithm is developed. Further, a computer program is developed that uses tabu search for weight minimization of two-dimensional framed structures. The program, written in the FORTRAN computer language, performs search, structural analysis, and structural design in an iterative procedure. The program is used to optimize the weight of three previously designed frames including threestory/three-bay, nine-story/five-bay, and 20-story/five-bay steel moment resisting frames. The program demonstrated its capability of optimizing the weight of these medium size frames in a reasonable amount of time without requiring engineer interference during the search. The structural weights for the three frames are reduced by an average of 23.4% from their original design weight.