Breach Discharge Estimates and Surface Velocity Measurements for an Earth Dam Failure Process Due to Overtopping Based on the LS-PIV Method
- 53 Downloads
Measuring the surface velocity and breach outflow discharge is a challenge in earth dam-break experiments. To solve this problem, large-scale particle image velocimetry (LS-PIV), a non-intrusive approach to measuring surface velocities, was applied in earth dam-break experiments. In this paper, two dam-break experiments were conducted in a large flume, and LS-PIV was used to measure the surface flow velocities of the dam breach. The flume was 50 m long, 4 m wide and 2 m high, and an idealized, non-cohesive, homogeneous earthen dam was placed in the middle of the flume. Three pressure sensors were used to measure the water depth over time. In addition, three high-speed digital cameras and two industrial cameras were used to record the dam breach process. The measured velocities were applied to evaluate the breach outflow discharge. Acceptable agreement was obtained between the discharges estimated with the LS-PIV and water level change methods. The surface velocity field was also obtained, and a dam crest cross section was selected to analyze the process of surface velocity change. Moreover, a convenient and simple formula was introduced to rapidly estimate breach discharge at the dam crest cross section. Finally, based on the Manning formula and surface velocity, the shear stress of the breach bottom was computed and discussed. The findings of this paper validate the accuracy and reliability of the LS-PIV technique for dam-break experiments and suggest that it is a reliable and advantageous technology for dam failure experiments.
KeywordsLS-PIV Dam-break Surface velocity Outflow discharge Shear stress
Unable to display preview. Download preview PDF.
- 1.Wang, Z.: A numerical three-dimensional non-cohesive earthen dam breach model. Ph.D. dissertation, Utah State University (2005)Google Scholar
- 5.Jodeau, M.; Paquier, A.; Hauet, A.; Le Coz, J.; Thollet, F.; Fournier, T.: Effect of a reservoir release on the morphology of a gravel bar: field observations and 2dh modeling. In: RCEM2007 (2007)Google Scholar
- 6.Hauet, A.; Creutin, J.D.; Belleudy, P.; Muste, M.; Krajewski, W.: Discharge measurements using Large Scale PIV under varied flow conditions, recent results, accuracy and perspectives. In: Ferreira, A., Leal, C. (eds.) River Flow, pp. 1829–1833 Taylor & Francis/Balkema, The netherlands (2006)Google Scholar
- 14.Fread, D.L.: National weather service models to forecast dam-breach floods. In: Starosolszky, O., Melder, O.M. (eds.) Hydrology of Disasters, pp. 192–211. James and James, London (1989)Google Scholar
- 15.Singh, V.P.: Dam Breach Modeling Technology, pp. 27–40. Kluwer Academic, Norwell (1996)Google Scholar
- 18.Al-Riffai, M.; Nistor, I.; Vanapalli, S.; Orendorff, B.: Overtopping of earth embankments: sensitivity analysis of dam breaching using two numerical models. In: Proceedings of 60th Canadian Geotechnical Conference, Ottawa, ON, Canada, pp. 1213–1220 (2007)Google Scholar
- 21.Al-Riffai, M.: Experimental study of breach mechanics in overtopped noncohesive earthen embankments. Ph.D. thesis, University of Ottawa, Ottawa (2014)Google Scholar
- 23.Christensen, J.L.; Herrick, L.E.: Mississippi river test, vol. 1. Rep. DCP4400/300, Straza Div, AMETEK, El Cajon (1982)Google Scholar
- 26.Rantz, S.E.: Measurement and computation of streamflow: Volume 2. Computation of discharge. Technical report, USGS (1982)Google Scholar