Experimental study on performance of GRS bridge abutment with flexible face

Based on the experimental study on performance of geogrid-reinforced soil (GRS) bridge abutment with flexible face under static load, the effects of offsets distance, D, between abutment foundation and panel of retaining wall on the ultimate bearing capacity of GRS bridge abutment, deformation characteristics, strain of geogrids and earth pressure are comprehensively and comparatively analyzed. The test results show that the ultimate bearing capacity of GRS abutment exhibits a remarkable increase tendency with the increase of D/H_L (H_L, height of geogrid-reinforced retaining wall) before D/H_L=0.4 for GRS retaining wall with the length of geogrids supposed to be equal to the height of GRS abutment, and the maximum ultimate bearing capacity can be obtained when D/H_L=0.4, which is followed by a significant decrease while Dis greater than 0.4H_L. Before failure happens to GRS abutment, the settlement of abutment foundation and top surface of GRS behind abutment tends to be linear and the differential settlement reaches the lowest level when D/H_L=0.4, and the ratios of horizontal deformation of panel to the height of lower wall are less than 1%. Moreover, horizontal deformations at top of lower walls are significantly greater than those in the middle and at the bottom of lower walls. Additionally, the maximum values of strains of geogrids occur and keep to be away from panel with the increase of D/H_L, and the strain level of geogrids in the lower wall and upper wall is almost the same as that when D/H_L=0.4. Therefore, the optimum performance of GRS bridge abutment can be obtained simultaneously.