ABSTRACT
Skewed bridges are known to be more susceptible to girder unseating than straight bridges. This increased vulnerability has been attributed to the out-of-plane movements of the girders. One of the major factors that affect the seismic response of skewed bridges is the Soil-Structure Interaction (SSI). The effects of SSI and skew angle applied simultaneously have not been explored in the past. In this investigation, 1:20 scale straight and skewed bridges were subjected to seismic excitations. The ground motion was simulated based on the NZS 1170.5 design spectrum for shallow soil condition (Class C). The bridges were fixed on a shake table to simulate the idealized fixed base case and placed on compacted sand to include the influence of SSI. The effects of SSI on the girder and footing displacements, and rotation of the girder were discussed. The findings provide useful insight into the response of skewed bridges including the effects of SSI.
