Author(s): Matthew C. Halso; Frederic M. Evers; David F. Vetsch; Robert M. Boes

Linked Author(s): David Vetsch, Robert Boes

Keywords: Dam breach; Zoned dam; Embankment dam; Material scaling; Overtopping

Abstract: The overtopping of an embankment dam or dike can result in formation of a breach, which may result in a catastrophic flood. Experimental research on zoned embankment breaching has been rare, and the morphodynamic processes that lead to failure of each zone remain not well-understood. A challenge for experimental research of zoned embankment breaching is scaling from prototype to model scale. Froude scaling of material from prototype earthen embankments results in model material that may not be morphodynamically similar to that of the prototype. This can affect the rate of material erosion and may cause a model zone to fail due to a different process than the corresponding prototype zone. As a reference for this study, a prototypescale zoned earthen embankment dam has been designed. The prototype dam contains three zones: shell, filter, and core. After assessing multiple methods for scaling that have been used in previous experimental hydraulics research, a model dam was designed and constructed by scaling each material zone based on the expected failure process of the prototype zone. A laboratory overtopping breach experiment of the model dam was then performed. A unique failure process was observed for each zone, beginning with a breach channel forming through the shell due to progressive surface erosion, and ending with the core breaking due to cantilever rotation. The experiment demonstrated that the applied scaling approaches allowed for successful representation of the expected failure processes during the overtopping failure of a zoned embankment dam.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p0448-cd

Year: 2023