Experimental investigation of geogrid-reinforced and pile-supported embankment at bridge approach

The geogrid-reinforced and pile-supported (GRPS) embankment and the geogrid-reinforced filling technique are employed to treat the bridge approach in loess area so as to reduce the differential settlement and alleviate the bump at the end of the bridge approach. Moreover, the earth pressure on the surfaces above and below the geogrid along the central axis and shoulder of the embankment are measured as well as deformation of the geogrid. The results show that the load on the soil between piles can be reduced effectively due to the soil arching and tensioned membrane effects. In the central axis of the embankment, most of the load is transferred by the soil arching and the tensioned membrane effects, but the tensioned membrane effect is not obvious. At the road shoulders, the tensioned membrane effect increases efficiently and the load is transferred by the soil arching effect together with the tensioned membrane effect. The effect of load transfer is significant at the bridge approach and decreases gradually with the increase of distance from bridge abutment.