Development of CCHE2D embankment break model

Authors: JIA, YAFEI - University Of Mississippi; Hunt, Sherry

Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/5/2016
Publication Date: 9/1/2016
Citation: Jia, Y., Hunt, S.L. 2016. Development of CCHE2D embankment break model. Transactions of the ASABE. 59(4):805-814.

Interpretive Summary: Dam and/or levee breaches often occur due to overtopping or internal erosion. Dam and/or levee breaches can be detrimental to downstream residential communities and infrastructure not only from an economic standpoint but also from a public safety standpoint. To gain knowledge in how a breach develops, engineers and scientists rely on physical modeling and observations made during the erosion process. Simplified computational models are also beneficial as they can be used to simulate the failure process. Although computational models do not require the expense of physical models, physical models are helpful in validate dam and/or levee failure scenarios. The goal of this study was to develop a computational tool that could be compared to experimental data collected from physical models of dam failures. Computational models will provide engineers with tools in analyzing real world embankment breach. These models could improve flood warning systems and help in the development of inundation maps and emergency action plans for floodplain managers and dam/levee engineers.

Technical Abstract: Earthen embankment breach often results in detrimental impact on downstream residents and infrastructure, especially those located in the flooding zone. Embankment failures are most commonly caused by overtopping or internal erosion. This study is to develop a practical numerical model for simulating overtopping and embankment breach process. To achieve the goal, the key physical-empirical dam breach mechanism of earth embankment is adopted and implemented into CCHE2D flow and sediment transport model. A special function describing the shape of the breach channel profile is introduced which significantly simplifies the breach modeling work. The developed model is validated using physical model data. The simulated breach hydrograph, headcut migration, and breach embankment profiles agree well with the observed data. Because this is a 2D model, the development makes it possible to simulate breach in a more complex condition and study multiple embankment breaches at the same time which broadens the applicability of the embankment breach model significantly.