Effects of Vehicle Suspensions on the Response of Highway Bridges

The effects of heavy vehicles with leaf-spring and air-spring suspensions on the dynamic response of short-span highway bridges are considered. The vehicle models consist of a leaf-sprung, four-axle articulated vehicle, and a similar vehicle fitted with air suspensions and hydraulic dampers. These two vehicle models are combined with three different bridge models to predict dynamic bridge responses, using the method described in Chapter 12 . Two surface roughness profiles are used on each bridge: a step-up at the entrance, and a pseudo random profile. Dynamic response increments are used to compare the effects of the two vehicles on the bridges. The air suspended vehicle is found to cause significantly lower dynamic bridge responses than the leaf-spring suspended vehicle.