PREDICTION OF BEACH PLANFORMS WITH LITTORAL CONTROLS.

Abstract

Three numerical models representing shoreline response are described and applied to a number of problems of coastal engineering interest. Included are: a one-line explicit model, a one-line implicit model, and a two-line explicit model. Simplified refraction and diffraction schemes are incorporated into the models. The models allow grid elements to be activated and deactivated as sand is initially deposited in or the last sand removed from a grid at a jetty inclined to the shoreline. Example applications of shoreline response are presented to illustrate the utility of the model including: permeable versus impermeable jetties, shoreline perturbations caused by jetties which are aligned with the incoming waves versus jetties perpendicular to shore, shoreline response inside a groin compartment and the effect of a littoral barrier. In addition, the one-line implicit model is applied to predict the shoreline response in the vicinity of an offshore breakwater at Channel Islands Harbor, Calif. where sediment is accumulated and dredged periodically.