Analytical Solution for Consolidation of Vertical Drains-Impervious Columns Multiple Composite Foundation under Nonuniform Distribution of Initial Pore Pressure

Abstract

Based on the axisymmetric model, the consolidation control equations based on the assumption of equal strain are established for the vertical drains-impervious columns multi-composite foundation consolidation problem, and the analytical solutions are given for the drains-impervious columns multiple composite foundation consolidation with trapezoidal, rectangular, positive triangular and inverted triangular distribution of initial pore pressure. Through the degradation study and comparison with the existing analytical solutions. Using the derived consolidation analytical solution for parameter analysis, the consolidation characteristics of multivariate composite foundation are studied. The results show that: the non-uniform distribution of initial pore pressure has a significant effect on the consolidation of combined composite foundations, the trapezoidal distribution is faster than the rectangular distribution, the positive triangular distribution is the slowest and the inverted triangular distribution is the fastest. The smaller the initial pore pressure value at the base of the soil layer and the larger the vertical permeability coefficient of the soil, the faster the consolidation. The consolidation rate of the foundation increases with the increase of the replacement rate of impervious columns and the compression modulus. Compared with the foundation of a single pile type, the consolidation rate of combined composite foundations can be significantly increased. The rate of consolidation of the foundation increases with the increase in the replacement rate and compression modulus of impervious columns.