Shoreline changes behind detached breakwater

Abstract

A series of experiments were conducted to study shoreline changes caused by the presence of a detached breakwater under the influence of pure wave action. The breakwater length, B, and its distance from the initial shoreline, X, were the two main parameters investigated. The study analyzes the effect of these two factors on shoreline changes. The experimental data show that (1) the size of a salient, X s, increases with B, but decreases with X; and (2) the deposition area of the salient, A, increases with both B and X for X ≤ B. However, further increase in X (X > B) will lead to a reduction in A. Based on the experimental results, the study proposes a criterion to demarcate the formation of a tombolo from that of a salient. The data also show that the width of the tombolo is directly proportional to B and inversely proportional to X. Finally, a new relationship for estimating the sand deposition area is obtained, and published data from the literature are used to verify the new relationship. © ASCE.