Braking effects on vehicle-bridge interaction

When analyzing the impact of vehicle braking on a bridge, it becomes evident that the bridge’s deflection increases significantly compared to when a vehicle is in constant motion. The magnitude of this deflection is influenced by the Vehicle-Bridge Interaction (VBI) phenomena, which is significantly activated by road roughness. This road roughness instigates specific dynamics in the vehicle, accentuating the VBI. Our study introduces a probabilistic model to quantify this amplification factor due to a vehicle’s hard braking at the bridge’s mid-span across various road roughness categories. The amplification factor is defined as the ratio between maximum deflections during vehicle braking and those when the vehicle is at a consistent speed. It’s estimated considering parameters like the vehicle’s mass, velocity, natural frequency, and damping. For our VBI model, we utilized the finite difference method to discretize the coupled governing equations. Here, the vehicle is represented as a two-degree-of-freedom system, accounting for both its bouncing and pitching motions. The model’s computational efficiency facilitated extensive analyses where parameters were chosen via the Latin Hypercube sampling method. Ultimately, we validated our model outputs against real-world bridge displacement measurements under varied conditions.