Seismic stability of geosynthetic-reinforced soil integral bridge

Abstract

The seismic stability of the conventional-type bridge, comprising a pair of cantilever-type abutments (e.g., gravity-type or L-shaped RC structure) supporting a girder on their top via fixed and movable bearings with the unreinforced backfill, is rather low. With Integral Bridges, the girder is integrated to a pair of RC abutments. A new type, called the GRS Integral Bridge, comprising a girder integrated to the top of a pair of RC facings with the backfill reinforced with geogrid layers connected to the facings, has a much higher seismic stability. The seismic stability increases by cement-mixing part of the reinforced backfill. By analyzing the results of shaking table tests on three Integral Bridge types by the one-degree-of-freedom dynamic theory, it is shown that the seismic stability increases with an increase in the dynamic strength, the dynamic ductility and the damping capacity.