A computational model of rockfill dam breaching caused by overtopping (RoDaB)

• Published in: Journal of hydraulic research Vol. 42; no. 2; pp. 197 - 206
• Main Authors: Franca, M. J., Almeida, A.B.
• Format: Journal Article
• Language: English
• Published: Delft Taylor & Francis Group 01.01.2004; International Association for Hydraulic Research
• Subjects: breach modelling; computational model; Dam break; Earth sciences; Earth, ocean, space; Exact sciences and technology; Hydrology. Hydrogeology; rockfill dams; floods; models; breccia; reservoirs; rupture; sedimentary rocks; propagation; management; carbon; erosion; sulfur; geometry; rockfill dams; methodology; clastic rocks
• ISSN: 0022-1686; 1814-2079
• DOI: 10.1080/00221686.2004.9728382

The outflow hydrograph from a dam failure is a boundary condition of a dam break flood model used on the downstream valleys risk management. Limited research has been made on the rockfill dams breaching process and there are no specific models to this type of structures yet. This paper describes a lumped model for the computation of the outflow hydrograph due to a Rockfill Dam Breaking named RoDaB. The methodology is based on the governing equations of reservoir routing and depletion, and breach erosion. Results obtained from experimental tests performed in a laboratory flume were considered to fulfil the phenomenological aspects to which does not exist any analytical approach so far. The erosion process from the dam breach is modelled as a function of two erosion parameters and of the breach final geometry dimensions obtained from the experiments. Finally, the model RoDaB is applied to a rockfill dam, with characteristics typical of this type of structure, and the results are compared with the ones from the BREACH model.