Analytical solution for consolidation of a composite ground with impervious multi-long-short piles

The impervious multi-long-short piles-reinforced ground is a new type of composite ground technology. The equations governing the consolidation of the surrounding soils within the composite ground are derived under instantaneous load. The analytical solutions are then developed for the consolidation of the composite ground based on the one-dimensional consolidation theory of a double-layer ground. The comparison of the consolidation rates from the proposed analytical solution with the FEM is made to verify the correctness and accuracy of the proposed analytical solutions. Parametric study is conducted to investigate the consolidation behavior of this new type of composite ground using the proposed analytical solutions. The results show that the consolidation rate of the composite ground with impervious multi-long-short piles increases with the increase of the area replacement ratio and the constrained modulus of the long piles. The area replacement ratio and the constrained modulus of the short piles have insignificant influences on the consolidation rate of the composite ground. When the short piles have shorter lengths, the variation of the length of the short piles has little influences on the consolidation rate of the composite ground. The consolidation rate increases with the increase of the length of the short piles when the short piles are long enough. Furthermore, it increases with the increase of the constrained modulus of the soil bellow the tip of the short piles.