Bridge bearings are products disposed between the top of the abutment or pier and the bottom of the girder. It has three basic features. The first one is the supporting capability against vertical and lateral loads. The second one is the horizontally mobile capability that can permit the expansion and contraction with temperature and the creep of the bridge girder. The last one is the rotational capability that can permit the rotational deformation at the fulcrum caused by the girder bending during vehicle pass.
In recent years, in addition to these basic functions, bearings have been responsible for the isolation function and the damping function to enhance the overall seismic capacity of bridges during the earthquake. Therefore, since the Hanshin-Awaji Earthquake has happened, bridge spanning the road around the high standards, such as highways and national roads have been adopted to increase the rubber bearing with the high isolation capability and damping function.
We describe the structure, the characteristic, the design and quality control method of the rubber bearings.