Aanleiding van het project
Within the dredging industry, it is common practice to generate fluid mud layers when executing projects in, for example, port areas. After generation of the fluid mud layer, it can then flow by gravity to deeper sections where it can be trapped. During flow, the fluidized layer will interact with the ambient water column and local hydrodynamic forcing (i.e. tidal currents or waves). Interaction of the fluidized layer with the water column can lead to an increase in turbidity of the water. The turbidity plume is important to be evaluated prior to project execution to estimate and mitigate environmental impacts of the dredging activities.
Normally, extensive model simulations are needed to predict the stability and fate of the fluidized layer, and thereby the impact of these dredging operations. However, during the planning and engineering phases preceding the actual dredging operations, time is limited, and extensive model simulations are often not a viable approach. Therefore, the need exists to rapidly assess the impact of dredging operations, using a model that correctly represents the relevant physical processes.
While this tool focuses on safe navigation and quality of the water body, knowledge and tools are directly applicable to “Building with mud” and “Nature-Based” applications in the interface area between fluid and soil or fluid to soil behaviour. This project contributes to the general topic of beneficial and sustainable use of sediments for water infrastructure, flood safety, nature biodiversity and resiliency, which are global critical societal challenges with high priority in the Dutch Government and Dutch Private Sector agenda (BV Nederland).
Doel van het project
Develop a rapid assessment numerical tool to assess the environmental impacts of fluidized sediment layers induced by a moving turbidity source, and validate and transfer of the tool to the private sector (Boskalis) for direct application.
Omschrijving van de activiteiten
The innovative aspect of this project lies within the nature of the numerical tool, which enables consultants and engineers to rapidly assess the impact of dredging operations. Currently simple empirical less accurate tools or with or (on the other extreme) extensive model simulations are utilized to predict the stability and fate of fluidized sediment layers, and thereby the impact of these dredging operations.
This tool will correctly represent the key physical processes, yet allowing quick first order assessment. Such tool is very much needed but currently missing within the private sector.
Two main project phases can be distinguished:
1) Development and verification of the numerical tool to model fluidized layer flow and interaction with the water column. The generic tool developed will be based on the Deltares 1DV model.
2) Validation of this tool on specific real dredging operation.
– Definition of approach: Q1 2018
– Model development: Q2 & Q3 2018
– Model validation: Q3 & Q4 2018
1 Rapid assessment numerical tool 2018
2 Report describing physics and functionalities of numerical tool 2018
3 Publication (scientific journal/conference paper or presentation) about tool development and functionality 2018 / 2019
Generic numerical tool and report Boskalis; Deltares; potentially: other dredging companies, researchers, consultancy engineering firms; potentially students during MSc classes. Boskalis through application in multiple projects per year (tender and engineering phase)
Deltares, through TKI website, publication, short courses, university curricula (e.g. TUDelft Sediment Dynamics course)
Publication (International) Researchers, practitioners ( consultants, contractors), port authorities, governmental departments. Deltares and Boskalis through international conferences and seminars, or via presentation / communications with own clients.