Displacement of Bridge Abutment Under Earthquake Loading

Bridge abutments may experience significant displacements during earthquakes. A two-dimensional model has been developed considering sliding and overturning displacement and 1) strain dependent soil stiffness and soil damping and 2) horizontal and vertical time dependent seismic load. The displacements are computed from the static equilibrium position where the seismic backfill force increments are considered for determining the active earth force acting behind the abutment wall. This means that the permanent displacement increment occurred if the acceleration acts towards the backfill and the abutment wall moves away from the backfill. The total displacement at the top of bridge abutment is calculated by adding the sliding and overturning displacements. An application of this model is presented, for a real abutment.