Study on the Stress and Deformation Laws and Work Principles of the Pull-pile Supporting Structure in a Deep Foundation Pit

In combination with the field monitoring data, PLAXIS3D finite-element software was used to numerically model the pull-pile supporting structure in a deep foundation pit. This structure was compared to the single-row pile support structure in order to learn more about the pull-pile supporting structure's force and deformation characteristics and how it works. The study found that the cumulative horizontal displacement curves of the supporting piles are integrated into an "upward convex" shape. The bendingmoment curve of the front-row piles presents an "inverted S" shape, and the bendingmoment curve of the back-pull piles presents a "bow" shape. The "back-pull-pile effect" can improve the unbalanced distribution of positive and negative bending moments in single-row piles by changing the stress condition of the soil. In other words, the pull-pile supporting structure has good safety and serviceability and can well control the lateral displacement of the foundation pit.