Numerical study of the mechanical behavior of fine- grained dredged sediments
In the last few decades dredging activities have experienced a significant growth. An efficient way to manage the dredged material is to reuse it to reclaim coastal confined containment facilities. When fine-grained sediments are involved, hydraulic dredging is a common, highly appreciated choice. This technology causes the dredged mud to sediment at very high water-to-solid volumetric ratios and then undergo dramatic deformations during consolidation. The paper presents the results of a numerical study conducted simulating the whole filling-consolidation process. The soil behaviour was modelled adopting the well-known Modified Cam-clay model, in conjunction with a strongly non-linear void ratio:permeability law. A series of parametric analyses was performed to investigate the influence of the hydro-mechanical properties on the dredged mud behaviour during the hydraulic filling and the subsequent consolidation process. The numerical results emphasize that the design of the filling works can significantly benefit from a deeper knowledge of these processes.