Comparative Analysis of Structural Behavior of a Four-Span Parker Truss Bridge Subjected to Vertical Loads

This study investigates the structural performance of a six-span Parker steel truss bridge under vertical loading conditions. Unlike conventional constant-depth truss systems, the Parker truss configuration is characterized by a variable-depth geometry, which is designed to enhance structural efficiency by aligning the height of the truss with the distribution of the bending moment. In this research, a six-span Parker truss bridge with a total length of ۳۰ meters was modeled, featuring span-specific heights of ۵ m, ۷ m, and ۹ m to provide optimal stiffness and load-carrying capacity. A two-dimensional finite element model was developed in Abaqus to analyze the response of the structure under a vertical load applied at specific nodes. The study evaluates the stress distribution, focusing on the von Mises stress, and the resulting vertical displacement characteristics across the multi-span system. The numerical results demonstrate the effectiveness of the variable-depth Parker configuration in redistributing internal forces and minimizing deformations compared with constant-depth truss systems. The findings provide significant insights into the structural behavior, load-path efficiency, and overall stability of Parker truss bridges, confirming their suitability for medium-to-long span applications. This research establishes a fundamental deterministic baseline for further structural health monitoring and reliability assessments of variable-depth steel truss bridges.

کلیدواژه ها:

Parker steel truss bridge ، load-carrying capacity ، structural behavior