Extraction of Nonlinear Hysteretic Properties of Seismically Isolated Bridges211 from Quick-Release Field Tests

摘要

The overall objective of this task was to develop nonlinear models foruse in211u001eseismic vulnerability assessments of isolated bridges. The report describes the 211u001edevelopment of an optimized procedure to perform such as assessment. To develop 211u001ethe procedure, the authors first identified the properties of interest of the 211u001eseismic isolators, then modeled the hysteretic characteristics of the bridge-211u001eisolator system. An analytical solution for the response of a bilinear SDOF 211u001esystem to quick-release excitation was derived. Data form two different quick-211u001erelease tests were used to test the procedure. The predicted vs. observed test 211u001edata were compared and showed good agreement. Thus, the authors concluded that 211u001equick-release field test data could be successfully used to extract nonlinear 211u001ehysteretic roperties of seismically isolated bridges.