SETTING THE FIBER MODEL FOR ESTIMATING THE ALLOWABLE DISPLACEMENT OF STEEL BRIDGE PIERS BASED ON CYCLIC LOADING EXPERIMENTS

The 1995 Hyogok-Ken Nanbu earthquake promoted widespread research efforts consisting of both experimental and analytical studies for the purpose of understanding the performance of steel bridge piers under seismic loads. The 1996 revised seismic design specification stipulated that ductility design method be used and performance be estimated on a nonlinear dynamic analysis using a hysteretic restoring force model. The fiber model uses a stress-strain hysteretic restoring force model and therefore can consider changing axial forces within a rigid frame. For this reason the fiber model is considered more accurate.