Dikes in the Netherlands often have a grass cover on the upper outer slope, the crest and the inner slope. Full-scale tests for the hydraulic loads on grass covers are performed either with wave loads on the outer slope, or wave overtopping flow over the crest and inner slope. This has resulted in different formulas for the flow velocity on the outer slope, compared to the flow velocity on the crest an inner slope. A uniform description of the flow velocity from the outer slope, to the crest and the inner slope is desirable.
Figure 1 Grass and clay erosion tests in the Delta flume tests at Deltares
Aim and approach
The aim of the project is to develop a uniform description of the flow velocity on the outer slope and crest of dikes. Data is available of large-scale model tests that will be executed in the summer of 2026 at Deltares. The model set-up contains grass on the outer slope and partly on the crest. Analysis of this data can help to improve our understanding of the flow on the outer crest line and the formulas for the flow velocity that can be used for the design and safety assessment of dikes.
Conditions
The graduate project is executed at Deltares in collaboration with the University of Twente and TU Delft. An internship-fee is available of €550 per month. The student is expected to be at Deltares in Delft for a minimum of 1, preferable 2 days per week.
If the student starts on time, they can also visit the Deltaflume experiments. However, starting after the experiments is also possible.
