PEER Reports

Seismic compression is defined as the accrual of contractive volumetric strains in unsaturated soil during strong shaking from earthquakes. While ground deformations from seismic compression have been reported in the literature , it contains few case histories in which the amount of ground deformation was known accurately from pre– and post–earthquake surveys. In this report, two such case histories are documented in detail and analyzed. Both case studies involve deep canyon fills in Santa Clarita, California, an area strongly shaken by the Northridge earthquake (peak accelerations on rock...

This report describes an experimental and theoretical study of the feasibility of using fiber reinforcement to produce lightweight, low-cost elastomeric isolators for application to housing, schools, and other public buildings in highly seismic areas of the developing world. The theoretical analysis covers the mechanical characteristics of multi-layer elastomeric isolation bearings in which the reinforcing elements, normally steel plates, are replaced by a fiber reinforcement. The fiber in the fiber-reinforced isolator, in contrast to the steel in the conventional isolator (which is...

A comprehensive Bayesian methodology for developing probabilistic capacity and demand models for structural components and systems is formulated. The methodology is employed to develop probabilistic models for reinforced concrete (RC) columns and multi-bent bridges. The probabilistic models are used to objectively assess the seismic fragilities of RC structural components and systems, in particular, of highway bridge systems.

The approach seeks to properly account for both aleatory and epistemic uncertainties. The probabilistic models developed are similar to deterministic capacity...

As a part of an experimental program investigating the effects of a variable axial load on the seismic behavior of bridge piers, six scaled re inforced concrete bridge columns with circular sections were tested at the Structural Laboratory of the University of Southern California (USC). The primary experimental parameters were the axial load and loading pattern. The loading program included a combination of a constant, proportionally or nonproportionally variable axial load and a monotonic or cyclic lateral displacement. The objectives were to study the effects of different loads and the...