Wave Forces and Overtopping on Crown Walls of Rubble Mound Breakwaters: an Experimental Study

The scientific progress of our understanding of the interaction between coastal structures and the sea has greatly improved in the recent years. The present state of knowledge includes structural and financial optimization of the structures based on reliability evaluations. The first requirement for such an evaluation is a mathematical formulation of the related structural failure modes. For rubble mound breakwaters several new reliable design formulae have been developed over the last decade but at least one major task still remains unsolved - the assessment of the wave loading and hence the stability of rubble mound breakwater crown walls.

This background motivated the initialization of the present study on wave imposed forces and wave overtopping on crown wall structures. The two subjects where investigated through an excessive parametric model study involving more than 370 long duration test series in the coastal laboratory at Aalborg University.

Based on analyses of experimental data a design method for assessing the maximum wave forces on the vertical face of the crown wall structures has been developed as well as new and more versatile design equation for the related overtopping discharges.

The stability of crown wall structures has also been investigated and a new methodology for the evaluation of the geodynamic response of the foundation is presented.