Abstract
The occurrence probability distributions of astronomical tidal level at 96 ports in Japan are calculated with four major tidal constituents. The distribution shapes are able to be classified into several categories mainly depending on the locations by the cluster analysis. The encounter probabilities of siliding and overturning, and expected sliding quantities of the present breakwaters for the durable years are computed in the probabilistic design theory with the estimated tidal probabilities. The encounter probabilities estimated with four major tidal constituents become smaller than those estimated with a simple cos-shaped tidal change in the shallow water area.
