Beach Nourishment Respons At Behind Submerged Structure

Abstract

In recent years, Indonesia beach is faced to erosion and abrasion problems. One of an alternative can be applied to solve these problems is beach nourishment. Beach nourishment need large volume of sediment filler. For reducing of sediment filler, then the sediment filler is protected by submerged structure. The problems, beach profile at behind submerged structure after beach nourishment reach to equilibrium condition is not yet understood. The objective of this research is to indentify beach profile behind submerged structure for several wave and structure parameters. This research conducted in Hydraulic and Hydrology Laboratory, Engineering Research Centre, Gadjah Mada University using of physical modeling. Equilibrium beach profile form at behind submerged structure influenced by deep water wave steepness (Ho/Lo) and depth relative (Rc/hs). The greater value of Ho/Lo and Rc/hs the greater the retreat of beach profile. Wave steepness can be used to indentify direction of sediment movement.