Riprap stability for deep water, shallow water and steep foreshores

In the Rock Manual [2007] two sets of equations for the determination of rock stability in breakwaters armour layers are presented. One set is the original formula presented by Van der Meer [1988], valid for deep water conditions. This set uses the parameters Hs and Tm. The other set is an adaptation of these formulae, using the parameters H2% and Tm-1,0, and is recommended for shallow water conditions. Tests by Van Gent et al. [2003] have lead to a calibration coefficient slightly different than the original Van der Meer values. Recently the second author [Mertens, 2007] has reanalysed the datasets of Van der Meer and Van Gent, corrected some of the numbers, and explained a part of the differences. This paper tried to unify both sets of formulae and come to one single equation.Hydraulic EngineeringCivil Engineering and Geoscience