BARDEX II: Bringing the beach to the laboratory – again!

Abstract

Masselink, G, Turner, I.L., Conley, D.C., Ruessink, B.G., Matias, A., Thompson, C., Castelle, B. and Wolters, G., 2013. BARDEX II: Bringing the beach to the laboratory – again!Proto-type laboratory experiments are particularly useful in coastal research when forcing parameters are modified in a way that is impossible to achieve in the field, and where installation and maintenance of instrumentation requires absence of waves. In 2008, the Barrier Dynamics Experiment (BARDEX) took place in the Delta Flume, the Netherlands. This project, funded by Hydralab III, focused on the effect of varying wave, sea level and beach groundwater conditions on a gravel beach (D50 = 10 mm). In 2012, a similar project was carried out, referred to as BARDEX II, this time funded by Hydralab IV and on a sandy beach (D50 = 0.42 mm). During the experiment, a 4.5-m high and 70-m wide sandy barrier was constructed in the flume with a lagoon situated to the landward. The barrier was instrumented with a very large number (> 200) of instruments and subjected to a range of wave conditions (Hs = 0.8 m; Tp = 4–12 s) and varying sea and lagoon water levels. Five distinct test series were executed over a 20-day period: series A focused on beach response due to accretionary/erosive wave conditions and a high/low lagoon water level; series B investigated the effect of a lower sea level on nearshore bar dynamics; series C simulated tidal effects; series D addressed the swash/overtopping/overwash threshold; and during series E the beach-barrier system was subjected to an extended period of energetic overwash conditions. This paper will describe the experimental design and the test programme during BARDEX II.