The Earthquake Engineering Online Archive

Mechanical characteristics of base isolation bearings for a bridge deck model test

Kelly, James M.; Buckle, Ian G.; Koh, Chan Ghee

UCB/EERC-86/11, Earthquake Engineering Research Center, University of California, Berkeley, 1986, 54 pages (530/K38/1989A)

This report describes the mechanical characteristics of rubber bearings designed for a base-isolated bridge deck model which represents a typical highway bridge superstructure. Two different forms of isolation systems were used in the test program: (1) elastomeric bearings made from natural rubber layers and reinforced with steel plates and (2) elastomeric bearings with a lead plug on a vertical axis to enhance damping. To satisfy the dynamic similitude laws for the model, the bearings were unusually slender by current code specifications and outside the range of height-to-width ratios commonly accepted for stability of elastomeric bearings in the United States. Static compression and shear tests, cyclic shear tests at different compression loads, and a series of shaking table tests were undertaken at the Earthquake Engineering Research Center of the Univ. of California at Berkeley to establish fundamental stiffnesses, buckling loads, and dynamic performance of the bearings.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-86-11.pdf (1 MB)