Influence of Uncertain Factor in Breakwater Design to Encounter Probability of Failure

Probabilistic errors are not considered in the present breakwater desing method. Such estimation errors are included in the computation of 1) deep water wave height, 2) wave transformation, 3) wave force on breakwater caisson, and 4) friction between the concrete caisson and rubble mound. The encounter probability of sliding and overturning failure and the expected sliding distance of caisson are mainly determined by these estimation errors as well as the structural type and tidal amplitude. The mean value of the encounter probabilities and expected sliding distance are inversely proportional to the safety factors used in the present breakwater design.