Non-linear finite element analysis of truss type steel bridges

Abstract

This work aims towards 3-D finite element analysis of truss type steel bridges using SAP 2000 software. Some of the recent research studies highlight the requirement of optimizing the Tied Arch truss type as it consumes considerable steel tonnage compare to the other truss types. Several modifications for the Tied Arch truss type are proposed in this research study, by introducing different truss types such as Strengthened Tied Arch and Pratt Type Arch truss types, in order to improve the Tied Arch truss type. Span vs. tonnage graphs were obtained for Strengthened Tied Arch and Pratt Type Arch truss types, and are compared with the different truss types such as Pratt, Modified Warren, Tied Arch, Inverted Arch and the Parker truss. Scaled down models of the Tied Arch and the Strengthened Tied Arch truss types were tested in the structural laboratory and then failure loads and failure modes of the test models were compared with the finite element analysis results. Geometric and material nonlinear analysis capabilities of SAP 2000 were evaluated by analyzing several finite element models. Failure analysis of Paragasthota Bridge was carried out by considering the dynamic analysis options available in SAP 2000. Dynamic analysis results were compared with the static analysis results and are presented in the report.