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Stiffness analysis of fiber-reinforced elastomeric isolators

Tsai, Hsiang-Chuan; Kelly, James M.

PEER-2001/05, Pacific Earthquake Engineering Research Center, University of California, Berkeley, 2001-02, 143 pages (400/P33/2001-05)

The reinforcing elements of multi-layered elastomeric isolation bearings, which are normally steel plates, are replaced by a fiber reinforcement. The fiber-reinforced isolator is significantly lighter and could lead to a much less labor-intensive manufacturing process. In contrast to the steel-reinforced isolator, which is assumed to be rigid both in extension and in flexure, the fiber-reinforced isolator is assumed flexible in extension, but completely without flexural rigidity. This report presents theoretical approaches for analyzing the compressive stiffness and bending stiffness of fiber-reinforced isolators having three types of geometry: infinitely long strip, rectangular and circular. The stiffness formulas of fiber-reinforced isolators are derived. The influence of fiber flexibility on the mechanical properties of fiber-reinforced isolators is studied, and it is shown that it should be possible to produce a fiber-reinforced isolator that equals the advantageous behavior of a steel-reinforced isolator.

Available online: http://peer.berkeley.edu/publications/peer_reports/reports_2001/0105.pdf