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Water Resour Manage (2013) 27:17511762
DOI 10.1007/s11269-012-0046-9
George Tsakiris & Mike Spiliotis
Received: 7 December 2011 /Accepted: 28 March 2012 /
Published online: 5 May 2012# Springer Science+Business Media B.V. 2012
Abstract The delineation of the areas exposed to flood hazard caused by a dam existence upstream and its possible failure needs a thorough analysis of the hypothetical dam break incident. The study presented in this paper focusses on the simulation of the dam breach formation and the calculation of the resulting outflow hydrograph using a semi- analytical approach. More specifically the method presented addresses the dam break incident of an embankment dam caused by overtopping. The analysis is based on the assumptions of constant vertical erosion rate for the formation of the breach and the parabolic shape of the breach. Two solutions are presented dependent on whether the capacity of the reservoir is considered prismatic or it is a power function of the water depth in the reservoir. Finally the proposed method is illustrated through the analysis of a hypothetical dam break incident.
Keywords Embankment dam . Dam break . Parabolic breach . Dam failure . Outflow hydrograph . Risk assessment
1 Introduction
Risk assessment studies are often carried out at the design stage for the construction of a new dam or during the testing of the health of an existing dam. Recent dam failures and the anticipated changes in climatic extremes indicate that more emphasis should be given by the scientific community to the causes of such failures and the accurate simulation procedures of dam failure.
In particular in case of embankment dam failure two common causes of failure can be studied in depth based on the findings of the last decades. These causes are the overtopping
G. Tsakiris : M. Spiliotis (*)
School of Rural and Surveying Engineering, Centre for the Assessment of Natural Hazards and Proactive Planning and Laboratory of Reclamation Works and Water Resources Management,National Tehnical University of Athens, 9 Iroon Polytechniou, 15780 Athens, Greecee-mail: [email protected]
G. Tsakirise-mail: [email protected]
Dam- Breach Hydrograph Modelling: An Innovative Semi- Analytical Approach
1752 G. Tsakiris, M. Spiliotis
and the piping. It has been now understood that the most crucial cause mainly with respect to time of failure is the overtopping.
Two are the main...