Vibration Characteristics of the PC Bridge Resonated to the Vehicles Generated by the Road Roughness Nearby the Expansion Joint

The authors performed a research using test trucks for a three-lane prestressed concrete bridge with 37.47m span that vibrated greatly. As the results of the research, the bridge had the frequency of the 1^st bending vibration (ca. 3.0Hz). And also, since the frequency and that of general vehicle's vibration (ca. 3.0Hz) is close, the bridge and vehicles had caused coupled vibration. Moreover it was clear that the bridge had vibrated greatly, only when the test truck had ran at the 2^nd slow lane. Because vehicle's suspension spring vibration had been generated by the road roughness with long space period nearby the expansion joint of the 2^nd slow lane. This paper describes the vibration characteristics of the prestressed concrete bridge coupled with the vehicle's vibration generated by the road roughness with long space period nearby the expansion joint. Besides, this study also examined the countermeasure to decrease the vibration by the dynamic response analysis due to running vehicle.