Evaluation for Sliding Stability of Breakwaters Considering Extreme Value Distribution of Offshore Waves and Several Storm Events in One Year

Abstract

All large waves in a service time lead to slide of breakwaters should be considered in the probability design method based on allowable sliding displacement. Previous studies assumed that the sliding failure is caused by annual maximum waves obtained from a given extreme value distribution. However, the second or third maximum wave comparable to the annual maximum can cause the sliding failure of breakwaters. This study evaluates the sliding stability of breakwaters considering several storm events in one year as well as the difference of offshore wave's extreme distributions. It was found that depending on the tail length parameter and extreme value distributions, the expected sliding distances are different and that previous methods estimating for sliding distance underestimate the expected sliding distance in some cases.