A laboratory study of overtopping and breaching of shingle barrier beaches

A laboratory study of overtopping and breaching of shingle barrier beaches.
Obhrai , C.and Powell, K.A. and Bradbury, A.
In: ICCE 2008 (31st International Conference on Coastal Engineering), 31 Aug - 5 Sept 2008, Hamburg, Germany. (2008)

Download:[img]
Preview
document citation PDF (78Kb)
Download:[img]
Preview
document citation PDF (1079Kb)
Official URL:http://icce2008.hamburg.baw.de
Abstract:Shingle and mixed sand / shingle beaches are widespread in many parts of the UK and Europe. These beaches are highly efficient and practical forms of coastal protection, however a shingle beach in common with any other type of beach, can suffer erosion and subsequent landward retreat of the shoreline. Consequently over a period of time a beach which was originally of satisfactory dimensions may be reduced to such an extent that it no longer constitutes an acceptable ‘line of defence’. Anticipating this state is clearly important if shingle beaches are to be managed effectively, and landward structures are not to be damaged by flooding. The classical dynamic equilibrium shingle beach profile has been described using the parametric model of Powell (1990). In theory, a dynamic equilibrium profile should develop for any given combination of wave conditions assuming that there is sufficient time and sediment available for the profile to form. This limitation means that the model is not valid for the prediction of overwashing and breaching of shingle barrier beaches. However it has been used to estimate profile performance in these circumstances (Buijs et al., 2005). An empirical framework, based on extensive fieldwork and physical model data was developed to predict the threshold for breaching of shingle barrier beaches (Bradbury, 2000). The field and model data used to develop the model related only to the shingle barrier at Hurst Spit. Bradbury et al (2005) found that model did not work so well when applied to other sites and concluded that use of the model outside the valid predictive range would result in the under prediction of overwashing. Further data was therefore required to test and extend the range of validity of the Bradbury model.
Item Type:Conference or Workshop Item (Paper)
Subjects:Coasts > Beach management
Coasts > Overtopping
Coasts > General
ID Code:202
Deposited On:13 Aug 2008 16:16
Last Modified:19 Jul 2017 07:49

Repository Staff Only: item control page