WAVE INTERACTION WITH BREAKWATERS INCLUDING PERFORATED WALLS

Abstract

During the past several decades, breakwaters including perforated walls have been introduced to resolve various problems associated with gravity-type breakwaters. In this chapter, firstly the mathematical models are described that predict various hydrodynamic characteristics of single- or multiple-row curtain-wall-pile breakwaters, the upper part of which is a curtain wall and the lower part consisting of an array of vertical piles. Their extension to irregular waves is also described. These models can also be used for curtain wall breakwaters or pile breakwaters by just removing the piles or by removing the curtain wall and extending the piles to the water surface, respectively. Secondly the mathematical model to predict wave reflection from a fully-perforated-wall caisson mounted on a rubble foundation is described, and its applicability to a partially-perforated-wall caisson and irregular waves is described. Thirdly a discussion is given for the calculation of the so-called permeability parameter, which represents the energy dissipation and phase shift of flows passing across a perforated wall.