1 Scope
This document specifies minimum requirements and test methods for elastomeric seismic
isolators used for bridges, as well as rubber material used in the manufacture of
such isolators.
It is applicable to elastomeric seismic isolators used to provide bridges with protection
from earthquake damage. The isolators covered consist of alternate elastomeric layers
and reinforcing steel plates, which are placed between a superstructure and its substructure
to provide both flexibility for decoupling structural systems from ground motion and
damping capability to reduce displacement at the isolation interface and the transmission
of energy from the ground into the structure at the isolation frequency.

