Influence of Parapets and Recurves on Wave Overtopping and Wave Loading of Complex Vertical Walls

Increasing sea water levels and storminess has intensified the need for structural measures to reduce wave overtopping without significantly raising the height of the wall. The use of recurves / wave return walls / parapets on vertical walls has been shown capable of significantly reducing wave overtopping, but may increase wave loading. Many parapet / recurve solutions have been used in practice, but no general guidance on their design are yet available. In this paper a significant amount of data have been gathered together under the EC CLASH project (EU project no. EVK3-CT-2001-00058) and studied more systematically for the first time. The paper discusses problems with systematic approaches to both overtopping and wave loading. It concludes with a simple reduction factor for wave overtopping depending on geometrical dimensions of the parapets and some guidance on wave loading for these cases.