Performance Estimates for Seismically Isolated Bridges

摘要: This report presents an analytical study investigating the performance of isolated bridge structure subjected to seismic excitation. Here is being assessed using following descriptors: maximum horizontal displacements and cumulative energy dissipated by individual isolator. Twenty different isolation systems are considered with varied parameters, namely, characteristic strength second-slope stiffness. Unidirectional bi-directional response-history analysis was performed considering nonlinear eight bins earthquake ground motions. Results used to: (1) determine increase in displacement a isolator due excitation utilizing coupled plasticity model circular yield function represent elements, (2) review accuracy current American Association State Highway Transportation Officials (AASHTO) equation for calculation structures which assumes unidirectional linearly increasing periods greater than 1-second, (3) develop prototype testing requirements isolators terms equivalent number harmonic cycles frequency based on observed demand imposed from numerical simulation events.