Analytical solution for consolidation of stone column-reinforced foundations considering radical and vertical flows in columns

Based on the proposed new method for solving consolidation degree of composite foundation and its expression, an analytical solution is obtained for the consolidation of composite ground with granular columns considering both radical and vertical flows in piles under multi-stage loading. In addition, the disturbance effect of column construction on the surrounding soil is also considered by introducing a linear function for the horizontal permeability coefficient of soils in the disturbed zone. The solution was analyzed by the degradation method and the comparison with the existing solutions. The results show that the obtained solution can be reduced to the solution considering both radical and vertical flows in piles under single-stage or instantaneous loading, the solution considering the coordination of vertical seepage and deformation of pile body, and the Terzaghi's one-dimensional consolidation solution for natural foundation. Thus, the correction and reasonability of the solution obtained is confirmed, and the solution does contribute to the development and improvement of the consolidation theory of composite ground. No consideration of the radial seepage in piles will overestimate the consolidation rate of the ground; the slower the foundation loading process is, the slower the consolidation of the foundation is. The proposed method provides a new idea for solving the consolidation degree of composite foundation.