2D OVERTOPPING AND IMPACT EXPERIMENTS IN SHALLOW FORESHORE CONDITIONS
AbstractThis paper introduces the 2D experiments conducted for the CREST project in the wave flume of Ghent University. The experiments focus on wave interactions with low-crested sea dikes fronted by a shallow foreshore and mildly to steeply sloping beaches, which is a very typical situation along the Belgian coast. Foreshore slopes of 1/20, 1/35, 1/50 and 1/80 were tested for a range of low to high energy wave conditions, a variation in wave steepness and two water levels. The main goal was to obtain a dataset in which the effects of the infragravity waves on the wave-structure interactions (i.e. wave overtopping and impact forces) can be studied. The tests included high spatial resolution surface elevation measurement tests, which is new for beaches including a dike in the inner surf zone. From the first results it became clear that the foreshore slope influences the wave transformation up to the dike toe. The influence is apparent comparing to existing (semi-) empirical models for prediction of the spectral wave period at the dike toe and wave overtopping at the dike crest. The high spatial resolution data show a steep increase in infragravity significant wave height in the very shallow area in front of the dike.
Aalborg University, 2018a. AwaSys webpage. www.hydrosoft.civil.aau.dk/awasys.
Aalborg University, 2018b. WaveLab webpage. www.hydrosoft.civil.aau.dk/wavelab.
Almar, R., Michallet, H., Cienfuegos, R., Bonneton, P., Tissier, M., Ruessink, G., 2014. On the use of the Radon Transform in studying nearshore wave dynamics, Coastal Engineering, 92, 24-30.
Altomare, C., Suzuki, T., Chen, X., T. Verwaest, T., Kortenhaus, A., 2016. Wave overtopping of sea dikes with very shallow foreshores, Coastal Engineering, 116, 236-257.
Altomare, C., Verwaest, T., Willems, M., Vanneste, D., Suzuki, T., De Roo, S., 2018. Multi-directional wave basin for shallow foreshore applications, Proceedings of the 7th International Conference on the Application of Physical Modelling in Coastal and Port Engineering and Science (Coastlab18), Santander, Spain, May 22-26, 2018.
Boers, M., 1996. Simulation of a surf zone with a barred beach; Part 1: wave heights and wave breaking. TU Delft Report, No. 96-5.
RÃ¸ge Eldrup, M., and Lykke Andersen, T., 2019. Estimation of incident and reflected wave trains in highly nonlinear two-dimensional irregular waves, Journal of Waterway, Port, Coastal, and Ocean Engineering, ASCE, 145(1).
Guza, R.T., Thornton, E.B., Holman, R.A., 1984. Swash on steep and shallow beaches, Proceedings of the Coastal Engineering Conference, 1984, 708-723.
Hofland, B., Chen, X., Altomare, C., Oosterlo, P., 2017. Prediction formula for the spectral wave period Tm-1,0 on mildly sloping shallow foreshores, Coastal Engineering, 123, 21-28.
Kamphuis, J.W., 1998. Long waves in flume experiments, Proceedings of 26th Conference on Coastal Engineering, 26, Copenhagen, Denmark, 1998.
Lykke Andersen, T., Clavero, M., Frigaard, P., Losada, M., Puyol, J.I., 2016. A new active absorption system and its performance to linear and non-linear waves, Coastal Engineering, 116, 236-257.
Mansard, E.P.D., Funke, E.R., 1980. The measurement of incident and reflected spectra using a least squares method, Proceedings of the Coastal Engineering Conference, 1980, 154-172.
MDK (Agency for Maritime and Coastal Services) - Coastal Division, FHR (Flanders Hydraulics Research), 2011. Masterplan Kustveiligheid - Kustveiligheidsplan (Coastal safety plan).
Ruessink, G., Michallet, H., Bonneton, P., Mouazé, D., Lara, J.L., Silva, P.A., Wellens, P., 2013. GLOBEX: Wave dynamics on a gently sloping laboratory beach, 7th International Conference on Coastal Dynamics, 1351-1362, 24-28 June, Bordeaux, France.
Streicher, M., Kortenhaus, A., Hohls, C., 2016. Analysis of post overtopping flow impacts on a vertical wall at the Belgian Coast, Proceedings of the 6th International Conference on the Application of Physical Modelling in Coastal and Port Engineering and Science (Coastlab16), Ottawa, Canada, May 10-13, 2016.
Streicher, M., Kortenhaus, A., Gruwez, V., Hofland, B., Chen, X., Hughes, S., Hirt, M., 2019. Prediction of dynamic and quasi-static impacts on vertical sea walls caused by an overtopped bore, Proceedings of 36th International Conference on Coastal Engineering (ICCE2018), Baltimore, Maryland.
Suzuki, T., Altomare, C., Verwaest, T., Trouw, K., Zijlema, M., 2014. Two-dimensional wave overtopping calculation over a dike in shallow foreshore by SWASH, Proceedings of 34th International Conference on Coastal Engineering (ICCE2014), Seoul, Korea.
van Dongeren, A.R., Battjes, J.A., Janssen, T.T., van Noorloos, J., Steenhauer, K., Steenbergen, G., Reniers, A., 2007. Shoaling and shoreline dissipation of low-frequency waves, Journal of Geophysical Research: Oceans, 112, C02011.
Van Gent, M.R.A., 1999. Physical model investigations on coastal structures with shallow foreshores: 2D model tests with single and double-peaked wave energy spectra, Delft Hydraulics/Waterbouwkundig Laboratorium.
Van der Meer, J.W., Allsop, N.W.H., Bruce, T., De Rouck, J., Kortenhaus, A., Pullen, T., Schuttrumpf, H., Troch, P., Zanuttigh, B., 2016. EurOtop, 2016. Manual on wave overtopping of sea defences and related structures. An overtopping manual largely based on European research, but for worldwide application, http://www.overtopping-manual.com/manual.html.
Victor, L., Troch, P., 2010. Development of a test set-up to measure large wave-by-wave overtopping masses, Proceedings on the Third International Conference on the Application of Physical Modelling to Port and Coastal Protection (Coastlab10), Barcelona, Spain, September 28-October 1, 2010.
VLIZ (Flanders Marine Institute), 2018. The CREST project webpage. http://www.crestproject.be/en.