Structural Weight Optimization with Tabu Search

Optimization of structural weight is of particular importance for construction in space, moon, or mars since transportation of the structural elements to these sites is very costly. An optimized structure that satisfies the design requirements while utilizing minimum amount of material is especially suitable for construction in such remote areas and can result in significant savings in transportation costs. The Tabu Search method, a heuristic search technique, was selected for application to the structural weight optimization of skeleton structures. Further, a computer program was developed that uses Tabu Search for weight minimization of two-dimensional framed structures performing search, structural analysis, and structural design in an iterative manner. The program was used to optimize the weight of several frames of varying height including 3-story/3-bay, 9-story/5-bay, and 20-story/5-bay steel moment resisting frames. These frames had previously been designed to resist vertical and lateral loads. The same loads were used for the optimized weight design using the Tabu Search program. To improve efficiency of the method, several searches were performed with different search parameters and the duration of search was increased if needed. The program demonstrated its capability of optimizing the weight of these frames in a reasonable amount of time without requiring engineer interface during the search process. The search procedure was able to reduce the structural weight of these frames by 26.4%, 18.3%, and 25.5% respectively compared to their original design weights.