The Impact of a Bump on the Response of a Bridge to Traffic

There are numerous studies on the dynamic amplification factors caused by traffic
flow on a bridge. For short- and medium-span bridges, the road profile appears as a
dominant parameter on the bridge dynamic response. In theoretical investigations,
the road profile is usually modelled as a stochastic random process. However, this
approach does not take into account the high irregularities that are prone to develop
in the connection of the bridge to its approach, as result of a damaged expansion
joint and/or differential settlement. Most of research on dynamic amplification due
to traffic has focused in bending moment effects. This paper uses planar vehiclebridge
interaction models to assess the increase in shear effects at the supports that a
bump prior to the bridge may cause. Results for a range of bumps, bridge lengths,
traffic configurations and road conditions are discussed.