MECHANISM AND SETTLEMENT ANALYSIS OF PILE-SUPPORTED AND GEOGRID-REINFORCED EMBANKMENTS

As an effective and economical treatment for soft soil,pile-supported and geogrid-reinforced embankment has been used widely in the world.In the numerical analysis,subsoil and embankment treated by one pile are simplified as a circular column;distribution characteristics and dissipation process of the initial excess pore water pressure under instantaneous loading are analyzed using elastoplastic FEM considering consolidation process of the subsoil.Mechanical properties of geogrid and settlement of embankment are also studied.The influences of pile length,pile space and pile cap dimension on load sharing ratio of pile and embankment settlement are also investigated.It can be seen that the initial maximum pore water pressure takes place in the lower soil due to the load transformation from pile cap to soil.When the pile penetrates the soft soil,the settlement of embankment is dependent on the compression of upper soil between the piles.Otherwise,embankment settlement lies on the compression of soil beneath pile.Pile length is the main factor that effects the settlement of embankment;pile space and dimension of pile cap are followed.A case study is performed at last.