LARGE SCALE LABORATORY TESTS OF DUNE EROSION

An ongoing research program at North Carolina State University (NCSU) has investigated the viability of a mechanics based swash induced dune erosion model. Early work includes both small scale laboratory and field experiments. The overall objective of the experiments was to determine the relationship between the swash characteristics and dune erosion under a variety of conditions. A linear relationship between the specific swash force (per unit width of the dune) as defined by the bore depth and velocity, and the specific volume eroded has been documented for an individual swash (in the lab), Overton et al. (1988) and for a series of swash events (in the field) Fisher et al. (1987). Problems of scale, dune material and manner of construction in the field led to a series of experiments in the large wave tank at Oregon State University (OSU). The objective of the OSU tests was to investigate the relationship between the swash force and the volume eroded for two prototype scale dunes of different sand grain size.