Abstract:
Bracing systems have been widely used in steel and reinforced concrete structures for lateral load resistance. Minimum required stiffness, logical topology and material properties of these braces can be combined to determine an optimal bracing scheme. A classic methodology considering soil-structure interaction (SSI) is proposed in this paper to minimise the material requirement to brace steel frames. The optimisation algorithm is based on elimination of elements with minimal strain energy densities. The proposed optimisation algorithm was applied on a conventionally designed concentric steel frame structure. Non-effective quadrilateral steel elements from the braced bays were eliminated gradually and a final layout for the optimal topology was selected. It is shown that the modified structure saves 25.9 percent and 63.6 percent material, respectively, for bracing two bays and one complete frame in all its bays without considering SSI. The material saving increases further by considering SSI.