Abstract
Large settlements have often taken place in the backfill in back of bridge abutments during previous earthquakes. To alleviate this problem, it is proposed to geogrid-reinforce the backfill in back of conventional type bridge abutment and further to construct geogrid-reinforced soil retaining walls as bridge abutments. Shaking table tests were performed on small models of; 1) conventional RC abutment with unreinforced backfill; 2) grid-reinforced soil retaining wall as an abutment; and 3) and 4) conventional RC abutment with reinforced backfill, with and without reinforcement layers attached to the back of the RC structure. The importance of attaching reinforcement to the back of the RC structure in keeping the residual deformation and displacement of abutment small was demonstrated. It was also found that the reinforced soil retaining wall has a high seismic ductility, while the deformation should be reduced by some measures, such as preloading and prestressing.
