A LABORATORY STUDY ON WAVE OVERTOPPING AT VERTICAL SEAWALLS WITH A SHINGLE FORESHORE

Abstract

The existing empirical prediction formulae to determine the wave overtopping characteristics are mainly based on the laboratory measurements with the use of an impermeable foreshore slope in front of the structure. Recently, EurOtop (2016), an updated version of previous overtopping manual has been published with revised empirical equations to estimate mean overtopping discharge rates at plain vertical walls with and without foreshore.As past studies were mostly carried out at vertical seawalls on a fixed impermeable bed, little knowledge is available on the performance of these processes at coastal structures on a permeable shingle beach. This study presents the baseline overtopping characteristics at a plain vertical wall on an impermeable 1:20 foreshore slope, and compares the results with existing empirical predictions (EurOtop, 2016). In this paper, only the results on mean overtopping discharge and mean sediment rate at vertical walls are reported.