Performance of Ball Rubber Bearings in Low-Temperature Regions

This research is a complementary study to a recent experimental study on a newly developed seismic isolator called ball rubber bearing (BRB). BRB-type isolators can be easily manufactured similar to the standard elastomeric bridge bearings and can provide significant energy dissipation during an earthquake through friction provided by steel balls inside the cylindrical core. Structural response of BRBs at low temperatures has not been examined in previous research. In this research, behavior of BRBs exposed to different simulated weather conditions is tested under combined axial and cyclic lateral load. Comparison of room temperature and low-temperature test results indicates that the BRB can have slightly increased damping characteristics and horizontal stiffness in cold-weather conditions. This shift in performance has been included in the proposed design recommendations. (C) 2014 American Society of Civil Engineers