Three-Dimensional Modeling on Load-Transferring Mechanism of Rigid Pile–Net Composite Foundation

Abstract

The application of load-transferring mechanism is significant in the design of rigid pile–net composite foundations. A three-dimensional (3D) analytical model is adopted in this paper to analyze the load-transferring mechanism for the rigid pile–net composite foundation under the effect of uniform load. The multiple geosynthetic–reinforced cushion layer (MGRCL) is idealized as a typical thin plate with large deflection, and its bending stiffness matrix is also deduced with respect to the coupling effect of the multiple geosynthetic and gravel. Considering the actual 3D stress and displacement boundary conditions, deformation equations are developed for the MGRCL, and the corresponding solutions are also proposed with the consideration of the pile–soil interaction in two phases. A comparison between the analytical solution and the experiment results is performed, validating the accuracy of the proposed analytical method. Furthermore, a parametric study is conducted to investigate the influences of many factors on the load-transferring mechanism of the rigid pile–net composite foundation, including the equivalent modulus of the MGRCL, the stiffness of the soil adjacent the piles, the pile spacing, and the pile diameter. The results indicate that the stress ratio of pile to soil increases with the growth of the equivalent bending stiffness of the MGRCL and the pile spacing, and it decreases with the increase of the stiffness of the surrounding soil and the pile diameter.