Modelado de la morfodinámica de playas por medio de formulaciones de «Equilibrio».

Abstract

In this paper recent advances in the so-called «Equilibrium Beach» representation are presented. The equilibrium beach is defined as the hypothetical final shape that a beach would reach for a given constant wave forcing. Although this equilibrium shape is 95 R. Medina y otros Modelado de la morfodinámica de playas... not possible in nature, since the stationary state is never reach, this «ideal» concept is widely used since allows beach investigators to have an approximate, but realistic, representation of the beach morphology. Equilibrium beach consists of three elements, equilibrium beach profile, equilibrium plan form and equilibrium grain size distribution. Regarding the equilibrium beach profile, new developed models represent the profile in two different zones, allowing a better representation of the processes involved in the breaking and shoaling part of the profiles. These new models (Medina et al., 2000) also allow including the effect of the wave reflection from the beach and the tide. The most widely used formulation for representing the equilibrium plan form is the one proposed by Hsu and Evans (1989), recent advances in this area have been oriented to increase the capabilities of the formulation for predictive and design purposes (González y Medina, 2001). Finally new equilibrium grain size distribution formulations are presented. These formulations have been recently developed (Galofré y Medina, 2000) and give information on the sand distribution compatible with the existing wave conditions. 1.