ABSTRACT
ABSTRACT: Ensuring adequate post-earthquake operability of highway bridges is crucial for maintaining transportation networks which provide vital services after an earthquake. In highly seismic regions, reinforced concrete bridges are designed to undergo large inelastic displacements during earthquakes, leading to possible large permanent or residual displacements. These residual displacements are an important factor in determining post-earthquake functionality of a highway bridge. To mitigate the problem of residual displacement, methods of providing self-centering to structural reinforced concrete members have been developed for bridges and buildings and has been a subject of recent research both in the US and in Japan. Such systems use vertical, unbonded posttensioning to facilitate self-centering of the piers (i.e. cause minimal residual displacements) after cyclic loading with low hysteretic energy dissipation. A formalized performance-based earthquake engineering assessment methodology developed by the Pacific Earthquake Engineering Research (PEER) Center in California, USA is being used to assess quantitatively the possible benefits of self-centering systems for structural concrete bridge piers. Potential benefits of self-centering piers include reduced repair costs and reduced bridge closures.
