Author(s): S. Soares Frazao; M. Poncin; V. Paquier; B. Spinewine; Y. Zech
Linked Author(s):
Keywords: Dam break; Bank erosion; Finite volume; Geomorphology
Abstract: Numerous catastrophic events in recent history showed that the exceptional flood ensuing a dam-break is associated with strong bed-and bank erosion, and intense sediment transport. Those rapid geomorphic processes in turn may significantly influence the flow behaviour. The resulting dramatic changes in the valley geometry may increase enormously the human and environmental impact. The present investigation attempts to reproduce both experimentally and numerically the rapid morphologic changes caused by a dam break in a straight valley reach. At this exploratory stage, simplifying assumptions were taken such as an initially prismatic valley and the choice of non-cohesive uniform material for the banks. An accurate topographical survey of the valley after the dam-break was obtained by digital imaging measurement of the cross sections. Based on these experimental observations, a one-dimensional finite-volume numerical scheme was developed, including a simple bank-erosion mechanism. The encouraging qualitative agreement with the measured data opens motivating perspectives for the numerical modelling of severe transient geomorphic flow.
Year: 2001