Theoretical and Numerical Analysis on Geosynthetic-Reinforced and Pile Wall-Supported Embankment

Abstract

The vertical reinforcement (pile walls) is combined with the horizontal reinforcement (geosynthetics) to provide an economical and effective solution for ground treatment of high embankments constructed on soft soil. Theoretical and numerical analyses were conducted to investigate the interaction among geosynthetics, pile walls and soft soil. The differential settlement between pile wall and soft soil will generate soil arching in embankment fill. Soil arching and tensioned membrane of geosynthetics are combined to transfer embankment loads from soft soil to competent substratum (such as bedrock) through pile walls, which minimize the yielding of the soft soil and potentially reduce the total and differential settlements. The soil arching efficiency, the pile wall efficiency, the differential settlement of the embankment, and the distribution of tension force in the geosynthetics have been analyzed with the consideration of four major influencing factors: the elastic modulus of the pile wall, the tensile stiffness of the geosynthetics, the height of the embankment fill, and the area ratio of the pile wall. Some conclusions are drawn as a reference for the design and construction of geosynthetic-reinforced and pile wall-supported embankment over soft ground.