EVALUATION OF TOPOLOGICAL FORMS FOR WEIGHT- GN OF SINGLE-SPAN STEEL TRUSS BRIDGES

This paper reports a comparative study on design weight efficiency of single span steel truss bridge topologies subjected to gravity loads. The bridges configured according to nine distinct topological forms (namely, Pratt, Parker, Baltimore, Petit, K-Truss, Warren, Subdivided Warren, Quadrangular Warren and Whipple) are designed for minimum weight under various span length requirements of single span truss bridges, and the results obtained with these topological forms are compared. The optimization process for each bridge topological form requires achieving optimal sizing of members as well as determining coordinates of the top chord nodes such that the least design weight is attained for the bridge. The design constraints and limitations are imposed according to serviceability and strength provisions of ASD-AISC (Allowable Stress Design Code of American Institute of Steel Institution) specification. The optimization algorithm employed is based on simulated annealing method.