Comfort Analysis of Large-Span Continuous Girder Bridges to Moving Vehicular Loads

Abstract

To address the drawback of comfort evaluation on Highway Bridges due to moving vehicular loads, a large-span continuous girder bridge, namely Yilan Songhua River Highway Bridge, is studied in detail. The pedestrians comfort and riding comfort of the selected bridge under both single-vehicle and multi-vehicle are analyzed by our computer programs VBCVA (vehicle-bridge coupled vibration analysis) which is based on modal synthesis method and VCE (vibration comfort evaluation) which is based on existing common evaluation criteria. The peak accelerations of vehicles and the bridge are significantly influenced by the increase in bridge surface roughness as speed increases. Pedestrians acceleration induced by truck is larger than that induced by car. Except at the abutment span where the resonance speed is lower than other spans, the comfort of pedestrians at different locations of the mid-span are practically the same for various speeds. The riding comfort influenced by the truck on adjacent lane is dependent on the relative value between the dynamic response of the bridge and its roughness. For continuous girder bridges, because of the smaller dynamic response induced by the truck on adjacent lane compared to that induced by the roughness of the lane itself, the influence between adjacent lanes can be ignored. Finally, it is shown that the pedestrian comfort and riding comfort of the newly built Yilan Songhua River Bridge could meet the existing requirements in normal operation.