Analytical solutions for consolidation of stone column composite foundations considering time-dependent boundary and loading

Abstract

In response to the existing consolidation theory for stone column composite foundations which cannot consider the time-dependent loading and the well resistance effect of stone columns under time-dependent boundaries, a consolidation model that can reflect these characteristics is developed in this study, and the corresponding analytical solutions are obtained under permeable top surface with permeable bottom surface (PTPB) and permeable top surface with impermeable bottom surface (PTIB), respectively. In addition, the reliability of the proposed solutions is verified by comparing them with existing analytical solutions. Extensive calculations are then performed by the proposed solutions to analyze the consolidation behaviors of stone column composite foundations under time-dependent boundaries, the results show that the interface parameters have a large effect on the distribution of excess pore water pressure (EPWP) along the depth; for projects with longer construction time, the permeability of the top and bottom surfaces of the composite foundation has a smaller effect on the average consolidation rate. Finally, the proposed solution is applied to the settlement calculation in an actual engineering project, and the theoretical results show a general agreement with the measured data by considering the influence of the interface parameters.