Supplementary Files
Keywords
wave overtopping
hydraulic simulator
grass cover
dike
levee
breach
How to Cite
Abstract
A new Wave Run-up Simulator has been designed, constructed, calibrated and used for testing of the seaward face of dikes. The upper part of dikes or levees often have a clay layer with a grass cover. The new device is able to test the strength of the grass cover under simulation of up-rushing waves for pre-defined storm conditions. The cumulative overload method has been developed to describe the strength of grass covers on the crest and landward side of dikes, for overtopping wave volumes. In essence there is not a lot of difference between the hydraulic load from an overtopping wave volume or from an up-rushing wave. Therefore the hypothesis has been evaluated that the cumulative overload method should also be applicable for up-rushing waves. Tests on a real dike have been used to validate this hypothesis. The main conclusions are that the new Wave Overtopping Simulator works really well, but that the results on testing till so far has not yet been sufficient for a full validation of the method. More research is required. Furthermore, a new technique has been developed to measure the strength of a grass sod on a dike: the grass pulling device. Tests with this device showed that it is possible to measure the critical velocity (= strength) of a grass cover, which is much easier than performing tests with a Wave Run-up or Overtopping Simulator.References
Bijlard, R., G.J. Steendam, H.J. Verhagen and J.W. van der Meer. 2016. Determining the critical velocity of grass sods for wave overtopping by a grass pulling device. ASCE, Proc. ICCE 2016, Antalya, Turkey.
Slomp, R., H. Knoeff, A. Bizarri, M. Bottema and W. de Vries. 2016. Probabilistic flood defence assessment tools. FLOODRisk 2016.
Steendam, G.J., Van Hoven, A., Van der Meer, J.W. and Hoffmans, G. 2014. Wave overtopping simulator tests on transitions ans obstacles at grass covered slopes of dikes. ASCE, Proc. ICCE 2014, Seoul, South Korea.
Steendam, G.J., Y. Provoost and J.W. van der Meer. 2012. Destructive wave overtopping and wave run-up tests on grass covered slopes of real dikes. ASCE, Proc. ICCE 2012, Santander, Spain.
Steendam G.J., P. Peeters, J.W. van der Meer, K. van Doorslaer and K. Trouw. 2011. Destructive wave overtopping tests at Flemish dikes. Proc. Coastal Structures 2011, Yokohama, Japan.
Van der Meer, J.W., G. Hoffmans and A. van Hoven. 2015. Product 5.12 Analysis grass erosion in wave run-up and wave overtopping conditions. Report in project WTI Onderzoek en ontwikkeling landelijk toetsinstrumentarium. Deltares report 1209437-005.
Van der Meer, J.W., Y. Provoost and G.J. Steendam. 2012. The wave run-up simulator, theory and first pilot test. ASCE, Proc. ICCE 2012, Santander, Spain.
Van der Meer, J.W., B. Hardeman, G.J. Steendam, H. Schuttrumpf and H. Verheij. 2010. Flow depths and velocities at crest and inner slope of a dike, in theory and with the Wave Overtopping Simulator. ASCE, Proc. ICCE 2010, Shanghai.
Van der Meer J.W., G.J. Steendam, G. de Raat and P. Bernadini. 2008. Further developments on the wave overtopping simulator. ASCE. Proc. ICCE 2008, Hamburg, Germany.