Analytical Solutions for Desiccation of Fine-Grained Dredged Sediments

Abstract

Analytical solutions based on soil moisture suctions are presented for the desiccation of fine-grained dredged sediments driven by the atmospheric suction. It is assumed that diffusion governs water movement; hence the solutions are applicable to clayey and silty sediments only. Such solutions are more easily derived than those using moisture content as the primary variable, enabling a wider variety of cases to be considered. However, neither self-weight consolidation nor moisture inputs during desiccation, are accounted for. Sediment layers deposited on an impermeable base, with free drainage to the water table at the base, or on previously desiccated sediment layers with the same base conditions, are considered. The moisture characteristic curves of the sediments must be known to enable the suction profiles obtained to be converted to moisture content profiles. All of the solutions have been verified by comparison with the corresponding numerical solutions, and the single layer solutions have been shown to be consistent with limited field data.