VesweED

The aim the project VesweED (Influence of spatial vegetation structures on current- and wave-induced erosion processes on dunes) is to improve the understanding of the interaction between vegetation and dunes under hydrodynamic loading (wave and current). In particular, general relationships regarding the influence of individual vegetation parameters (rooting depth, patchiness) on erosion resistance and dune failure under stationary flow and non-stationary wave loading are to be derived. For this purpose, a geometrically and dynamically scaled surrogate vegetation model will first be developed, which will allow accurate process mapping in the experimental work while eliminating challenges due to the use of live vegetation. Experiments on overflow (at Institute of Hydraulic Engineering and Water Resources Management of RWTH Aachen) and wave impact (at Leichtweiß-Institute for Hydraulic Engineering and Water Resources of TU Braunschweig) with systematic variation of vegetation parameters will be conducted in a complementary manner as part of the experimental work. The use of the same measurement techniques and a uniform model setup ensure the comparability of the results. This also incorporates the assessment and modelling of dune related properties such as geometry, sedimentological grading and bulk density, in turn acquired through suitable geotechnical field sampling equipment. These in turn serve as a basis for the setup of numerical models which are used to investigate a large number of additional parameter variations within the framework of a supplementary numerical parameter study. The final step is a synthesis of the experimental and numerical results to a correlation model for the description of the dune failure and the erosion processes in dependence of the vegetation properties as well as a basic process understanding of the erosion behavior of vegetated and unvegetated dunes and the effect of dune vegetation.