Advances in one-dimensional numerical breach modeling of sand barriers

Advances in one-dimensional numerical breach modeling of sand barriers

Tuan, T.Q.
Verhagen, H.J.
Visser, P.J.

Civil Engineering and Geosciences

Hydraulic Engineering

2006-01-01

A hydrodynamic numerical model is formulated to describe the breach erosion process of sandy barriers. The breach flow is based on the system of unsteady shallow water equations, which is solved using a robust upwind numerical approach in conjunction with the Finite Volume Method (FVM). The hydraulic jump is considered as part of the breach flow, which escalates the scour hole development in the breach channel during the early stages. To reliably capture the jump, additional source terms are added to enhance the momentum balance in the flow equations. A three-layer refined scheme is used to compute the current profile and the associated sediment transport rate under the effects of the jump. A new approach to model the breach morphological development is proposed, which involves several new morphologic factors such as the channel characteristic width and the channel growth index. The model is capable of predicting the breach growth in both lateral and vertical directions, including the development of the scour hole. Some understanding of breach growth in coastal sand barriers in general can be drawn out based on the results of model simulation. The model is calibrated using the laboratory dike breach data of Caan (1996) and is verified against the field experimental data of the Zwin’s 94.

breaching
overwash
sand barrir

http://resolver.tudelft.nl/uuid:09eab1e8-e270-4c08-92aa-98ae7ef4c145

CUR- Gouda

Proceedings of the international conference on Sedimentation and Erosion (ICSE 2006), Amsterdam, Nov.

Institutional Repository

conference paper

(c) 2006 Tuan, T.Q., Verhagen, H.J., Visser, P.J.