Integral abutment bridges (IABs) have a continuous deck monolithically encased into abutment stem, and typically using single row of piles to carry vertical loads and accommodate longitudinal thermal deformation. Except for smooth pavement and low maintenance cost, IABs have also outperformed conventional seat-type abutment bridges in seismic performance due to increased redundancy, higher damping, and smaller displacements. However, lack of information on their seismic design and performance may have discouraged their use in high seismic zones. In this study, current research and implementation of IABs are comprehensively reviewed. IABs with steel-concrete girders provided by NYDOT are chosen for intensive seismic case study. Three-dimensional finite element models of IABs for nonlinear seismic analysis are elaborated to capture the behavior of components of superstructure, abutment stem, piles, backfill, etc. Pushover analyses are carried out to obtain the capacity curves. Through parametric studies, the effects of bearing are outlined. Conclusions and some recommendations are made for seismic evaluation and design practice of IABs.
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