Optimizing Single-Span Steel Truss Bridges with Simulated Annealing

This study presents applications of a simulated annealing integrated solution algorithm to the optimum design of single-span steel truss bridges subjected to gravity loadings. In the optimum design process of a bridge the members are sized simultaneously as the coordinates of the upper chord nodes are determined such that the least design weight is attained for the structure. The design constraints and limitations are imposed in accordance with serviceability and strength provisions of ASD-AISC (Allowable Stress Design Code of American Institute of Steel Institution) specification. A numerical example is presented, where optimum designs produced according to nine alternative topological forms of single-span truss bridges, namely Pratt, Parker, Baltimore, Pettit, K-Truss, Warren, Subdivided Warren, Quadrangular Warren and Whipple are compared for a selected span length of 600 ft (182.88 m) to quantify the influence of choice of a topological form on the final design weight of the bridge