A shoreline evolution model with a twin groins structure using unconditionally stable explicit finite difference techniques

Abstract

Beach erosion is a natural process that occurs when conveying sediment away from the shoreline is not balanced by depositing new material on the shoreline. This is a problem that is causing beach areas to decline. To avoid beach erosion and flooding, a sea wall and groin have been built. Shoreline evolution prediction is used to investigate the beach topography in the future. There are three phenomena give a large effect to the coastal structure such as the erosion, the accretion and the water level changes. To investigate of beach erosion and beach deposition is needed qualitative understanding of idealized shoreline response to the governing process. In this research, we introduce a governing equation of a one-dimensional shoreline evolution model when a couple of groins is added. The introduced model is a transient one-line model. The manipulation of physical parameters for the model is introduced. The setting method of the initial condition and the boundary conditions techniques when a couple of groin structure effect are also proposed. The traditional forward time centered space method and the unconditionally stable Saulyev finite difference methods are employed to approximate the incremental model in each year. The proposed numerical models give practically simulation for long-term shoreline evolution investigation. The proposed simulation can be used to predict the efficiency of a groin system construction in a local beach. The model is a tool for environment impact assessment of a installing groin structure project.