Parameters influencing seismic response of horizontally curved, steel, I-girder bridges

摘要

This study examines the influence of curved, steel, I-girder bridge configuration on girder end reactions and cross frame member forces during seismic events. Simply-supported bridge finite element models were created and examined under seismic events mimicking what could be experienced in AASHTO Seismic Zone 2. Bridges were analyzed using practical ranges of: radius of curvature;;girder and cross frame spacings;;and lateral bracing configuration. Results from the study indicated that: (1) radius of curvature had the greatest influence on seismic response;;(2) interior (lowest radius) girder reactions were heavily influenced by parameter variations and, in certain instances, uplift at their bearings could be a concern;;(3) vertical excitation more heavily influenced bearing and cross frame seismic response;;and (4) lateral bracing helped reduce seismic effects but using bracing along the entire span did not provide additional benefit over placing bracing only in bays adjacent to the supports.