A coastal Behaviour model

Abstract

A computer model for wave analysis, sediment transport computation and morphological process prediction along a coast has been developed as a master of science thesis. The very important factor in morphological processes, the wave propagation, has been analyzed using a fairly realistic mathematical model, viz.: ENDEC model, which considers ENergy DECay of random waves over an alongshore rather uniform, but cross-shore arbitrary varying topography. For sediment transport computation several formulae have been involved whereas sediment distribution over a direction normal to the coast has been presented based on Bijker and Van Rijn approach through a numerical procedure. The results of the mentioned wave analysis are locally applied in this numerical computation. Although, a random wave analysis was considered in the model, the wave characteristics in some location corresponding to the breaker point in regular waves were needed for sediment transport computation by the CERC formula. An investigation was carried out in order to find a criteria to determine the location on which the wave characteristics could be applied in the CERCformula as the breaker parameters. Since reliable prototype measurements on sediment transport are very difficult to obtain, a comparison analysis has been carried out on three sediment transport formulae. Bijker and van Rijn formulae were compared with the well-known CERCformula in this evaluation to verify the results of these two formulae. As an applicability investigation of the model a computer program has been made to predict coastal evolution near the breakwaters of a harbour. As an applicability investigation of the model a computer program has been made to predict coastal evolution near the breakwaters of a harbour. An abbreviate name was selected for this series of the programs as CBH model, which is an acronym for Coastal Behaviour computer Model.