Uncoupled Consolidation Analysis of Clay Deposits with Linearly Varying Characteristics with Depth

Abstract

Consolidation parameters, permeability and volume compressibility, are the classic and influential parameters in pore water pressure development and the settlement behavior of natural alluvial deposits. Permeability plays a major role in excess pore water pressure dissipation, while the volume compressibility coefficient determines the amount of consolidation settlement. The present paper focuses on an uncoupled consolidation formulation in order to emphasize the role of spatial variation of consolidation parameters and their influence on pore water pressure dissipation rate. Deterministic heterogeneity of permeability and volume compressibility was chosen to model the inherent variability of affecting parameters by considering a depth-decreasing trend for these parameters. A numerical implicit backward Euler scheme was adopted to solve the heterogeneous consolidation equation. The rate of change for permeability and volume compressibility with depth was studied to see their effects on the consolidation rate. It was found that the inherent variability of consolidation parameters should not be neglected as it may introduce an overestimation in the average degree of consolidation estimation, especially for highly variable alluvial deposits.