Semi‐Analytical Solution for Consolidation of Unsaturated Soil Composite Foundation Improved by Local Permeable Pile With Finite Hankel Transform

ABSTRACT The application of semi‐permeable columns, such as the pipe pile with holes, provides new insights for the selection of pile types in composite foundations. In this study, the axisymmetric consolidation model of unsaturated soil composite foundation (USCF) with local permeable pile by introducing the column‐soil interface parameters is established under the free‐strain assumption. By applying Laplace transforms, finite Hankel transforms, and their inverse transforms, a semi‐analytical solution is obtained, accounting for both radial and vertical flow. The effectiveness of the presented solution is verified by comparing it with governing equations and semi‐analytical solutions from existing literature. Furthermore, the consolidation behaviors of USCF with semi‐permeable columns are studied under various influencing factors. The results indicate that an increase in the column‐soil interface parameter and area replacement ratio accelerated the dissipation of excess pore pressures, thus shortening the time required for its complete dissipation. It is noteworthy that when the column‐soil interface parameter exceeds 10, its effect on the acceleration of excess pore pressure dissipation becomes negligible.