Structural Integrity Assessment of a Four-Span Parker Truss Bridge with a Damaged Member under Combined Horizontal and Vertical Loading

Parker truss bridges, characterized by their variable-depth geometry, are widely used in bridge engineering due to their structural efficiency and ability to span relatively long distances. However, the structural performance of these systems can be significantly affected when local damage occurs in one of the members, especially under complex loading conditions. This study investigates the structural response of a four-span Parker truss bridge with a single damaged member subjected to combined horizontal and vertical loads. A detailed finite element model was developed to evaluate the influence of the damaged member on stress distribution, displacement patterns, and overall structural stability. The results indicate that the presence of damage leads to noticeable changes in the internal force paths and causes stress redistribution within the truss system. Under combined loading conditions, the interaction between lateral and vertical forces produces an asymmetric deformation pattern and increases stress concentration in specific regions of the structure, particularly around the lower chord and central joints. The analysis highlights the sensitivity of variable-depth truss systems to member degradation when multiple loading components act simultaneously. The findings provide valuable insights into the structural behavior and robustness of Parker truss bridges and emphasize the importance of considering combined loading scenarios in structural assessment, maintenance planning, and safety evaluation of truss bridge infrastructures.

کلیدواژه ها:

Parker truss bridge ، Finite Element Analysis ، Structural Damage