Numerical Analysis on Influence of Shield Construction on Adjacent Pile Foundation

3D-elastoplastic model is established based on GTS about shield close through the adjacent bridge pile foundation impact,which is used to study the whole interaction among pile cap,group piles,soil and tunnel by simulating the actual construction process.The results show that shield construction can cause displacement on strata.The soil body around the tunnel has a displacement tend which causes the horizontal displacement of the piles.The deformation and stress states of piles are closely dependent on not only the construction process,but also on the position,length and quantity of piles.