Investigation of Vertical Stiffness Degradation due to Lateral Deformation of Elastomeric Bearing and Corresponding Impact Factor Variation of Slab Bridge

In the present study, the impact factor variation of a slab bridge supported by laterally deformed laminated bearings was investigated through 3D FE moving load analysis. The neo-Hookean model was adopted for the bearing, and the slab deck was modeled with solid elements. From the analysis results, the bearing vertical stiffness decreased slightly until a lateral deformation ratio of 0.3, which is defined as the ratio of the lateral displacement to the total thickness of the bearing. However, the stiffness decreases above this ratio, showing a 10.87% decrease for a deformation ratio of 0.7. The peak impact factor is almost the same up to a deformation ratio of 0.7. However, a larger deformation ratio leads to a precipitous increase in the impact factor, which is an increase of approximately 10% under the 1.0 ratio, which is the maximum deformation ratio considered in this study.