Author(s): Yong-Hui Zhu; P. J. Visser; J. K. Vrijling
Linked Author(s): Yonghui Zhu
Keywords: Breach; Erosion; Clay-dikes; Model; Headcut; Mass wasting
Abstract: The process of breach erosion in clay-dikes (i. e. dikes constructed with cohesive soil) is described. This process consists of five stages. In the first three stages the breach just eats itself into the dike with flow shear erosion and headcut erosion being the main causes for the breach development. At the end of Stage III the dike is completely broken through. For the last two stages, breach erosion takes place mainly laterally. The breach width increases markedly due to continuous flow shear erosion and discrete mass failure from the breach side slopes. The extent of vertical erosion in these two stages relies mainly on the geometrical and material conditions of the dike. Depending upon these conditions, three types of breaches can be distinguished for Stages IV and V of the breach erosion process in clay-dikes. A brief outline of a mathematical model based on this five-stage breach growth process is presented. The model has been tested with the data of three laboratory experiments performed in HR Wallingford (Hassan et al., 2004). The agreements between the model predictions and the experimental data are good.
Year: 2005