DAMAGE PROGRESSION ON BREAKWATERS

Abstract

An experiment is described consisting of seven relatively long-duration breakwater damage test series. The test series were conducted in a flume using irregular waves. New damage measurement techniques were developed and damage development data were acquired for breaking wave conditions. Wave height, wave period, water depth, storm duration, storm sequencing, and stone gradation were all varied systematically. The experiment yielded relationships for both temporal and spatial damage development. The relations by Melby and Kobayashi (1998a,b) for predicting temporal variations of mean damage with wave height and period varying with time in steps are shown to describe damage reasonably well (within one standard deviation) for new test series, although damage initiation is consistently underpredicted by more than a standard deviation. The prediction is shown to improve significantly if the initial profile adjustment is accounted for in the test series with relatively small cumulative damage.