The Earthquake Engineering Online Archive

Dynamic and failure characteristics of Bridgestone isolation bearings

Kelly, James M.

UCB/EERC-91/04, Earthquake Engineering Research Center, University of California, Berkeley, 1991-04, 82 pages (515/K34/1991)

High-damping Bridgestone isolation bearings are used in several recently completed base-isolated bearings in Japan. These isolators carry the vertical load, provide low horizontal stiffness, and generate significant damping, thus obviating the need for additional mechanical energy-dissipating mechanisms. These bearings are produced in several sizes up to very large diameters and are guaranteed by the manufacturer to be able to sustain shear strains of around 400 percent. Four of these high-damping bearings were tested at the Earthquake Engineering Research Center of the Univ. of California at Berkeley to verify the dynamic properties and failure mechanisms. Each bearing was subjected to five cycles of vertical loading centered at three levels of vertical pressure. Each bearing was subsequently tested under monotonic loading to failure under the four levels of vertical pressure. The significant aspects of the bearing failure are discussed.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-91-04.pdf (5 MB)