Comparative study on wave overtopping reduction performance on a novel dike-front wave dissipation basin and other engineering measures

A dike-front Wave Dissipation Basin (WDB) is proposed as an engineering measure to reduce wave overtopping discharge over sea dikes. Flume tests are conducted to quantify the overtopping reduction effectiveness of the WDB and to compare it with other engineering measures. The tests are carried out under various wave conditions, water levels, and cross-sectional sea dike configurations. Comparisons are made among the overtopping reduction performances of a Simple Sloped Dike (SSD), a sea dike with a wave dissipation berm, an SSD with WDBs of different lengths, an SSD with a detached breakwater (BW), and an SSD with a Stilling Wave Basin (SWB). Results demonstrate that the application of the WDB leads to significantly lower overtopping discharge across a wide range of relative crest freeboards, including both negative and positive values. Empirical equations are proposed to estimate the overtopping reduction coefficient of the WDB. A comprehensive comparison is made among the functional characteristics of four types of engineering measures, i.e. WDB, berm, BW, and SWB. The findings of this study on the dike-front WDB present a promising approach to enhancing the resilience of sea dikes.