Geosynthetic-Reinforced Soil (GRS) integral bridge was developed and constructed for the first time in Japan. A pair of GRS retaining walls (RWs) are first constructed as the main component of a pair of abutments. After the deformation of supporting ground and backfill has taken place sufficiently, a RC full-height rigid (FHR) facing is constructed by casting-in-place concrete directly on the wall face wrapped-around with geogrid layers reinforcing the backfill in such that the facing is firmly integrated to the reinforced backfill. Finally, a girder is constructed with both ends structurally integrated to the top ends of the FHR facings. Due to very-high cost effectiveness with excellent performance against not only severe seismic loads but also long-term train loads requiring minimized maintenance work, this technolo-gy has been well accepted by railway engineers in Japan. Potential problems due to annual thermal de-formation and long-term concrete dry shrinkage of the girder and severe seismic loads become more seri-ous as the span becomes longer. Several measures were developed to alleviate these problems by performing a series of cyclic loading tests on a full-scale partial model comprising a FHR facing, a buffer zone and part of approach block. The relevance of the structural design and construction method was con-firmed by monitoring long-term performance of a GRS integral bridge with a span of 60 m.
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