The dynamics of a coast with a groyne system

This paper is a continuation of the paper with the same name, presented to the XIth Conference on Coastal Engineering by the first author [1], in which a mathematical theory was given about the behaviour of a coast after the construction of a groyne system. Now this paper extends the former paper theoretically and practically. 1. Theoretically : a computer program has been made in which the influeence of diffraction behind the groyne has been taken into account. 2. Practically : the coastal constants used in the theoretical model of the coast will be expressed in terms of wave height and wave direction based on the theory of SVASEK [2]. Results are given of computations with a coastal model, in which the coast is schematized to one line (one-line theory) and a model in which the coast is schematized to a beach line and an inshoreline (two-line theory). / The influence of changing wave conditions is investigated.