The effect of anisotropy on consolidation in a soil layer

In routine design, it is customary to use simplified one-dimensional consolidation theory to estimate the rate of settlement of buildings or other structures. The actual drainage conditions will differ significantly from the one-dimensional model, and the pattern of excess pore pressures and effective stress changes will be three-dimensional. Anisotropic soil conditions will also affect the consolidation response. In this paper, an analytical solution for consolidation of a cross-anisotropic soil layer is outlined. The solution is based on combined Laplace and Fourier transforms of the governing differential equations. Results of the analysis are presented showing the progress of consolidation for different loading conditions, shape of loaded area, and degree of anisotropy of the soil. The results are compared with those obtained assuming one-dimensional consolidation and significant differences between the two approaches discussed.