Numerical Simulation of the Influence of Bored Pile Construction on Adjacent Existing Pile Foundation

Abstract

The procedure of constructing the bored piles of a new bridge is simulated by using the three-dimensional finite element method. The variance of soil body stress, the deformation in each step of the construction, and the stress variance of the existing pile foundation are predicted. The following analysis results are obtained: (1) The construction of a new abutment affects the displacement and structure stress of existing bridge piles; (2) Every step of the construction process affects the displacement of the lower part of the foundation pit; (3) The influence of the first and third steps on the stress of the existing bridge piles is larger compared with other steps; (4) Given the surrounding soil disturbance it causes, the construction of a new pile foundation has little influence on the settlement of existing bridge piles. In view of these findings, the following guidelines are recommended: (1) The first and third steps should be given more attention as they are the key sources of risk; (2) The soil surrounding the existing pile should be reinforced by grouting; (3) Where possible, the strength of the retaining wall structure and brace should be improved; (4) A monitoring and warning system should be created based on information management.