Field Test Study on the Mechanical Behaviors of the Geosynthetic-Reinforced Pile-Supported Embankment and the Deformation of the Reinforced Bedding

Based on the test site of DK2059+560 Wu-Guang passenger dedicated line, the field test has been carried out to study the characteristics of the embankment stress and geogrid deformation of geosynthetics reinforced and pile supported embankment(GRPSE).The results showed that GRPSE was an effective method to deal with soft soil foundation,and the settlement was small.Obvious soil arching effect appeared on the reinforced bedding,the height of the soil arching of this site was about 1.6～1.9 m.Reaction force existed in the soil between piles.The stress on the soil between the piles and pile cap was uneven.The stress among the centroid of 4 piles was a little less than that between the middle of 2 piles.The stress of pile cap centroid was a little less than that of pile corner.The strain of the geogrid vertical to the pile cap edge was relatively large.The strain of geogrid near the centrid of soil among the 4 piles was a little small.For the double-layer geosynthetics,the sublayer suffered more loads and less sliding action than that of upper geosynthetics,the geosynthetic strain of the side slope was larger than that of the embankment center.Compared with British,Nordic,Japanese and German norms,the field measured results of the proportion of the embankment vertical stress and load was closer to the calculation results by German norm.