Abstract: In this paper, the consolidation problem of soft clay ground improved by granular columns with impeded boundaries is studied and the corresponding analytical solution is developed. Based on the solution and relevant computations, the influence of some major factors on the consolidation process is investigated and the relevant results are prepared in graph forms. It is shown that the main parameters affecting the rate of consolidation are Rv ,Rv ,Y,H/dw and s. The greater the value of Rv and Rv , the greater the rate of 1 2 1 2 consolidation of the composite foundation. But in comparison with the others, the permeability of the impeded layers has less influence on the rate of consolidation.