Abstract: By the analytical solution of the average excess pore water pressures in a composite ground with a floating impervious pile, an analytical solution is obtained for the consolidation of surrounding and underlying soils under variable loading. The validity of the proposed solution is illustrated by comparing the present solutions to the FEM results. The consolidation behavior of the surrounding and underlying soils is investigated using the current solutions. The results indicate that the consolidation rate of the surrounding soil is considerably larger than that of the underlying soil, and it increases with the increase of area replacement ratio and constrained modulus ratio of a pile to surrounding soil. The consolidation rate of the underlying soil is hardly influenced by the constrained modulus ratio and area replacement ratio when the area replacement ratio is located within the range recommended in engineering design, and penetration ratio of a pile is not large enough. The consolidation rate increases with the increase of the constrained modulus and area replacement ratios. There exist some critical values of the constrained modulus ratio and area replacement ratio, beyond which consolidation rates of the surrounding and underlying soils are insensitive to the variations of these two parameters. The consolidation rates of the surrounding and the underlying soils always increase with the increase of loading rate.

Key words: impervious pile, composite ground, consolidation, surrounding soil, underlying soil