Numerical Analysis Of Performance Of Geosynthetic-reinforced And Pile-supported Embankment

Compared with the conventional pile-surpported embankment, geosynthetic-reinforced and pile-supported embankment is widely used in engineering practice, withthe features of convenient construction, economical construction period, the relativelysmall total and diffrential settlement, lateral movement, etc. But the theory is far behindthe engineering practice due to the complexity of the mechanism of GRPS.In this theses, based on the model test of GRPS embankment, finite element softwarepackage ABAQUS is used to establish the models with and without the geogrid,respectively. After that the influences of geogrid on the embankment settlement and thepile soil stress ratio are studied. The numerical simulation results show that, whencompared with the conventional pile-supported embankment, the GRPS embankment caneffectively reduce settlement and the diffrential settlement of the embankment, andincrease the pile soil stress ratio; with the increase of the ground soil modulus, the pile soilstress ratio decreases.The finite element software package PLAXIS is utilized to build the fluid-structurecoupling model of GRPS embenkment, then analyze the performance development ofGRPS embankment with time by simulating the filling process and the control of the timeinterval in analysis. The research results show that, with the increase of the height of thefill, the excess pore water pressure and the embankment settlement increase, the lateralmovement of the toe of the slope also increases linearly during the construction period;after filling, the excess pore water pressure dissipates, the post-construction settlement ofthe embankment increases, while the lateral movement of the embankment reducesslightly during the post-construction.The parametric studies of the fill modulus, geogrid tensile rigidity, ground soilmodulus, cohesion and internal friction angle are performed to analyze their influence onsettlement, lateral movement, excess pore pressure of the embankment, and the axial forceof the geogrid. The research results show that, the ground soil modulus affects most onsettlement of the embankment; increasing the geogrid tensile rigidity can effectivelyreduce the lateral movement of the embankment.