ABSTRACT
Corrosion of bridge bearings can cause fatigue cracking from welds at the edge of the bottom plate. It is important that assessment of the condition of the bridge bearing for determining the soundness and load-bearing capacity of the bridge. In this study, the relationship between corrosion level and bearing function is clarified by FE analysis using a detailed bearing model. The behavior of bearing is applied to the full-bridge model as spring properties to study the differences in bridge response due to bearing corrosion. The analysis is targeted at corrosion on the contact surface of the spherical bearing (BP-A), which is in the largest number of steel bearings in service. Analysis of the corroded bearing showed that if the friction coefficients of the contact surfaces were increased, the bearing could not follow the displacement of the girder and rotated in the opposite direction to that of the intact bearing. The increased friction coefficient may cause fatigue cracks due to the increased compressive stress at the sole plate edge. Furthermore, this paper presents a cost-effective modelling of the bearing behaviour by representing it with two-directional and rotational springs and proposing spring constants and mounting positions according to the degree of corrosion.
