Derivation of governing equation for short-term shoreline response due to episodic storm wave incidence: comparative verification in terms of longshore sediment transport

The shoreline temporarily recedes significantly as incoming storm waves reach the beach and cause wave breaking energy dissipation. However, since existing change model simulates based on longshore sediment transport rate (LSTR) empirical formulae, which are derived using correlation between flux littoral drift, it is difficult to simulate this phenomenon, drafted with transverse drift. Therefore, in study, by applying concept of horizontal behavior suspended sediments, a set governing equations were that can short-term changes recedes, then recovers. Among three variables equation, two main physical related drift—the response factor recovery factor—can be obtained from median grain size. present third variable, actual speed was estimated comparison CERC formula discussed point view alongshore duration. This established introducing delay (DFLST), indicates how slowly sediments move relative current speed. It found inversely proportional square root scale factor. LSTR study compared observed values collected 25 beaches United States results four formulae. proposed equation expected widely used means predicting changes, unlike models, because consider temporal retreat due incidence.