Wave Overtopping and Stability Performance of Rubble Mound Breakwaters Exposed to Shallow Water Waves

Today, rubble mound breakwaters are used mainly for coastal protection or construction of harbour basins. For these structures, the typical wave conditions are breaking waves on shallow water. However, the typical design tools are mainly based on physical model tests with deep water wave conditions. Until the last decade, linear and mildly nonlinear wave generation methods existed which required a long foreshore to perform shallow water wave tests. Furthermore, no nonlinear wave separation methods existed. To measure the incident waves the tests would therefore have to be repeated without the model but with a effective passive absorption system.

This thesis investigates the applicability of existing wave generation methods. Guidelines are given for reproducing waves in the laboratory as close as possible to those found in nature. New highly nonlinear wave separation methods for regular and irregular waves are established. The work in this thesis makes it possible to perform tests on rubble mound breakwaters with shallow water waves without a long foreshore. Furthermore, the thesis investigates the stability and wave overtopping on the rubble mound breakwaters exposed to shallow water waves. The work has established prediction formulae for both topics, and these increase the reliability for shallow water waves. Furthermore, a formula for the notional permeability factor is established.