Verification procedures of performance-based design on the sliding stability of composite breakwaters

Estimating the probability distribution of deformation is essential in the performance-based design. As for composite breakwaters, the most significant performance requirement is usually the stability against sliding. Several criteria, such as the expected sliding distance and the exceedance probability for certain sliding distance during its lifetime, are proposed in order to optimize the design from an economical standpoint. In this paper, the verification procedures of the sliding stability are described and the most rational thresholds of these criteria according to the significance of the structures are proposed. This design method guarantees the structures for same stability irrespective of design conditions, such as extreme wave statistics, water depth, and tidal range. This procedure can be applicable not only to composite breakwaters, but also to other coastal structures.