Vehicle–Bridge Coupling Vibration Analysis of a Highway Pile–Slab Bridge Based on the Contact Constraint Method

To investigate the impact of vehicle load on highway pile–slab bridges, the contact constraint method is employed to treat the vehicle and the bridge as two independent subsystems. Through the formulation of point-to-surface contact and constraint equations, a vehicle–bridge coupling vibration analysis is performed, incorporating the effects of bridge deck roughness. The finite element method is utilized to construct the pile–slab bridge model, while the five-axis heavy vehicle model is developed based on the multi-rigid-body dynamics method. The analysis and computational results of the model reveal the effects of pier height, vehicle number, and the friction coefficient on the dynamic response of the pile–slab bridge. The results indicate that pier height significantly influences the dynamic response, and the appropriate pier height should be carefully determined during the design phase. The vertical displacement impact coefficient surpasses the design value derived from the specification, highlighting the need to consider the vehicle’s impact on the bridge. Furthermore, vehicle number and the friction coefficient significantly affect the longitudinal dynamic response and transverse acceleration response of the pile–slab bridge.