Analytical and Numerical Investigation of Internal Force Distribution in “Pile-Wall” Structures Based on Finite Difference Method

The “pile-wall” structural system involves the use of conventional temporary retaining piles as part of the underground structure during its operational phase. While this approach has been implemented in engineering practice, there is a significant research gap regarding the theoretical and numerical understanding of the internal force distribution and load-sharing characteristics of the “pile-wall” system, especially in relation to the reinforcement bars used as connection nodes at the interface between the retaining piles and basement walls. This study addresses this gap by proposing a composite structural model that integrates an elastic foundation beam with a continuous beam to simulate the mechanical behavior of the “pile-wall” system. A finite difference equation and computational method are developed to analyze the internal forces and displacements in the system during two key stages: excavation and completion of the basement wall construction. The analytical solutions are validated through comparison with finite element simulations, which show a high degree of consistency between the results. The main contributions of this study include the development of a reliable calculation method for analyzing “pile-wall” internal forces and providing new insights into the load-sharing mechanisms of the system. These findings contribute to a deeper understanding of the mechanical behavior of the “pile-wall” structure and offer a solid theoretical foundation for its broader application in engineering design.