ANALYSIS OF THE SEISMIC RESPONSE OF GEOSYNTHETIC-REINFORCED SOIL INTEGRAL BRIDGE ABUTMENTS

The geosynthetic-reinforced soil integral bridge combines the advantages of the integral bridge and geosynthetic-reinforced soil. However, there is great uncertainty about the dynamic response of this kind of new bridges. This paper presents the findings from a series of dynamic numerical simulations about the geosynthetic-reinforced soil integral bridges (IB-GRS) and compares the dynamic performance with three other types of bridges-the integral bridge (IB), geosynthetic-reinforced soil conventional bridge (CB-GRS) and simply supported bridge (CB). The results show that during an earthquake, the horizontal displacement of CB and CB-GRS is so large that the girder might collapse, while the horizontal displacement of IB and IB-GRS is much smaller. The IB-GRS bridge has the highest dynamic stability among the four bridge types. During the earthquake, the abutment bending moment and the axial force of geosynthetic layers have a remarkable increment. In the seismic process, the maximum axial force of each geosynthetic layer is found to take place inside the reinforcement across the slip plane of backfill, not at the end of the reinforcement near the abutment.