Author(s): Corinna Müller; Pierre-Jacques Frank; Willi H. Hager
Keywords: Dyke overtopping; erosion process; experimentation; Froude similitude; sediment-water flow
Abstract: This study deals with the erosion of granular laboratory dykes to allow for the prediction of the main dyke failure features, including the temporal advance of the maximum dyke height and the breach discharge. Two extreme scenarios are considered: (1) constant approach flow discharge; and (2) constant headwater elevation during the breach process, as the two extreme cases of prototype scenarios. Based on the previous research, the effects of three additional parameters, namely the up- and downstream dyke face slopes and the crest length, are considered by the so-called dyke shape parameter. Its effect is included in the governing dyke breach equations so that all relevant variables vary only as a function of discharge scenario, original dyke height, and sediment diameter. The breach process is described with typical images and plots, to highlight the various effects. The results allow for an estimate of the dyke breach characteristics based on Froude similitude.