Dynamic Response Analysis of Long-Span Continuous Bridge Considering the Effect of Train Speeds and Earthquakes

In this paper, the dynamic response analysis of long-span continuous bridge under earthquake and train load was simultaneously performed. In order to clearly reveal the mechanism of vibration coupling between vehicles and highway long-span continuous bridge, a numerical model including soil foundation, vehicle and bridge under inclined seismic wave was established utilizing finite element software. The dynamic response of the bridge with different wave incident angles and different train speeds was numerically analyzed. The results show that the wave incident angles have a significant effect on the dynamic response of the bridge, and with the increasing of the wave incident angle, the vertical displacement and velocity as well as the acceleration of mid-span constantly increase. While the dynamic response of the bridge does not increase always with the increasing of train speed, however, at a certain train speed, the dynamic response will reach the maximum. With the increasing of the train speed, the vertical displacements of mid-span points increase while the moments at mid-span reduce significantly when the soil–structure dynamic interaction was considered. The results can provide significant references to ensure the train safe running on the bridges under the earthquake.