EXPERIMENTAL STUDY INVESTIGATING VARIOUS SHOREFACE NOURISHMENT DESIGNS

Dirk-Jan Walstra, C. W. Hoyng, P. K. Tonnon, Leo C. Van Rijn

Abstract


This experimental study focuses on the morphological development of a near-equilibrium profile on which to types of shoreface nourishments are placed. As previous studies have indicated that the efficiency of nourishments is mainly influenced by water depth in which they are constructed, two cross-shore locations are considered for an accretive and an erosive wave condition. A nourishment relatively high in the profile covering the trough and a nourishment relatively low in the profile just seawards of the breaker bar were investigated. Detailed measurements of wave height, velocities and sediment transport are combined with the observed morphological development to identify the processes that dominate the morphological development. The results confirm that the cross-shore location of nourishment has a major influence. The nourishment in relative deep water reduces the erosion of the upper part of the profile by about 20% for the accretive condition and 40% for the erosive condition. The nourishment higher in the profile results in a reduction of the erosion volume of 60% for both wave conditions.

Keywords


shoreface nourishment; physical experiment; process measurements

References


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