Analysis and Design of Pile Foundation for Viaduct

Abstract

An efficient computational approach based on substructure methodology is proposed to analyze the viaduct–pile. The train–viaduct subsystem is solved using the dynamic stiffness integration method, and its accuracy is foundation–soil dynamic interaction under train loads. Verified by the existing analytical solution for a moving vehicle on a simply supported beam. For the pile foundation–soil sub system the geometric and material properties of piles and soils are assumed to be invariable along the azimuth direction. By introducing the equivalent stiffness of grouped piles, the governing equations of pile foundation–soil interaction are simplified based on Fourier decomposition method, so the three-dimensional problem is decomposed in to several two-dimensional axisymmetric finite element models. The pile foundation–soil interaction is verified by field measurements due to shaker loading at pile foundation top. In addition, these two substructures are coupled with the displacement compatibility condition at interface of pier bottom and pile foundation top. Finally, the proposed train–viaduct–pile foundation–soil interaction model was validated by field tests. The results show that the proposed model can predict vibrations of pile foundation and soil accurately, thereby providing a basis for the prediction of pile–soil foundation settlement.