Wear Evaluation on Slide Bearings in Expansion Joints Based on Cumulative Displacement for Long-Span Suspension Bridge under Monitored Traffic Flow

Abstract

Expansion joints of bridge superstructures generally suffer deterioration more severely than their main structures, and their actual service life is generally shorter than their design service life. This paper aims at evaluating the wear condition of slide bearings in expansion joints for long-span suspension bridges under monitored traffic flow in the operation stage. The spring element was introduced to model the expansion joint and verified by field load tests. The vehicle−bridge dynamic analysis on a steel truss girder bridge was realized in a nonlinear analysis system, in which the monitored traffic flow was simulated to investigate the back-and-forth displacements of expansion joints. Finally, the wear condition of slide bearings was evaluated by comparing cumulative displacements with the critical value specified by the wear criterion. Findings from this research led to the development of an approximate formula to estimate the cumulative displacement at the expansion joint for long-span suspension bridges, suitable for hand calculations.