Numerical Modeling of Breach Erosion of River Embankments

The process of breach erosion of river embankments depends on the interaction among flow, sediment transport, and the corresponding morphological changes. Levees often consist of noncohesive material with a wide range of grain sizes. The dam material is mainly eroded due to the transport capacity of the overtopping water. Both bed load and suspended load are of importance. For breach formation, the lateral erosion due to slope instabilities has a significant impact. A depth averaged, two-dimensional numerical model was developed to account for these processes. The sensitivity of the discharge through the breach related to different processes and material parameters was investigated and compared to experimental and field data. The results show that the most sensitive parameter of an erosion-based dike-breach simulation is the breach side-slope angle which determines the lateral erosion. The application of the described Model 2dMb to different embankment failures at the Elbe River illustrates its capability in simulating overtopping breaching.

[1]  Stephen Roberts,et al.  Explicit schemes for dam-break simulations , 2003 .

[2]  M H Chaudhry,et al.  COMPARISON OF COUPLED AND SEMICOUPLED NUMERICAL MODELS FOR ALLUVIAL CHANNELS , 1998 .

[3]  D. Rickenmann Hyperconcentrated Flow and Sediment Transport at Steep Slopes , 1991 .

[4]  Stephen G. Monismith,et al.  Evaluation of Advective Schemes for Estuarine Salinity Simulations , 2000 .

[5]  B. V. Leer,et al.  Towards the ultimate conservative difference scheme. IV. A new approach to numerical convection , 1977 .

[6]  Forrest M. Holly,et al.  2‐D Bed Evolution in Natural Watercourses—New Simulation Approach , 1990 .

[7]  P. K. Sweby,et al.  A high‐resolution scheme for the equations governing 2D bed‐load sediment transport , 2005 .

[8]  Zhaoyin Wang,et al.  Turbulent Structure of Water and Clay Suspensions with Bed Load , 1994 .

[9]  C. P. Skeels,et al.  Evaluation of some approximate Riemann solvers for transient open channel flows , 2000 .

[10]  L. Rijn Sediment Transport, Part II: Suspended Load Transport , 1984 .

[11]  C. Paola,et al.  Numerical simulation of aggradation and downstream fining , 1996 .

[12]  Dennis A. Lyn,et al.  Unsteady Sediment‐Transport Modeling , 1987 .

[13]  Deva K. Borah,et al.  Routing Graded Sediments in Streams: Formulations , 1982 .

[14]  L. Rijn Principles of sediment transport in rivers, estuaries and coastal seas , 1993 .

[15]  Robert J. Connell,et al.  Two-Dimensional Flood Plain Flow. I: Model Description , 2001 .

[16]  Ephraim M Sparrow,et al.  Advances in Numerical Heat Transfer , 1996 .

[17]  Francesco Macchione,et al.  Practical aspects in comparing shock-capturing schemes for dam break problems , 2003 .

[18]  David Beadman Civil Engineering Practice , 2003 .

[19]  Shinji Egashira,et al.  Coupled and Decoupled Numerical Modeling of Flow and Morphological Evolution in Alluvial Rivers , 2002 .

[20]  M. Jaeggi,et al.  Grain sorting processes , 2002 .