Mohamad Hidayat Jamal, David J. Simmonds, Vanesa Magar, Shunqi Pan


Coarse-grained beaches are particularly prevalent in the UK, composed of accumulations of either gravel, or mixed sand and gravel sediments. Understanding and predicting their morphological behaviour in response to short-term and long-term forcing has been the subject of recent research. Despite the focus on sandy beaches, it is important to understand that the balance of processes that govern different behaviour between sandy and gravel beaches. In this study we show how a public domain numerical model, XBeach, developed for sandy environments (Roelvink et al., 2009) can be modified for use in predicting the cross-shore profile changes of gravel beaches. Improvements investigated here include: use of Lagrangian interpretation of velocity in place of Eulerian for driving sediment movement; incorporation of Packwood’s (1983) pragmatic model of infiltration in the unsaturated area of the swash region; introducing of new morphological module based upon Soulsby’s (1997) sediment transport equation for waves and currents. These changes are suggested in order to significantly improve the application of this model to gravel beaches, especially with regard to swash velocity asymmetry which is responsible for development of the steep accretionary phase steep berm above waterline. The results from the model agree well with the measured experimental data and improve upon the results presented by Pedrozo-Acuña et al. (2006).


gravel beach; infiltration; sediment transport; XBeach

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Austin, M. J. 2005. Swash, groundwater and sediment transport processes on a gravel beach, PhD thesis, Loughborough University, U.K

Butt, T. and Russell, P. 2000. Hydrodynamics and cross-shore sediment transport in the swash-zone of natural beaches: A review, Journal of Coastal Research, 16 (2), 255-268.

Butt, T., Russell, P., Turner, I. L. 2001. The influence of swash infiltration-exfiltration on beach face sediment transport: Onshore or offshore?, Coastal Engineering, 42 (1), 35-52

Dodd, N., Stoker, A.M., Calvete, D., Sriariyawat, A. 2008. On beach cusp formation, J. Fluid Mechanics, 597, 145-169

Elfrink, B. and Baldock, T. 2002. Hydrodynamics and sediment transport in the swash zone: a review and perspectives, Coastal Engineering, (45), 149-167

Foote, M., Horn, D., Li, L. 2002. Measuring swash zone hydrodynamics and morphodynamic change – a high-resolution laboratory system using digital video, Journal of Coastal Research, SI 36, 300-316

Freeze, R.A. and Cherry, J.A. 1979. Groundwater, Prentice Hall Inc., Englewood Cliffs, NJ, USA

Heath, R.C. 1983. Basic groundwater hydrology, US Geological Survey Water Supply paper, 2220

Karambas, T. V. 2003. Modelling of infiltration-exfiltration effects of cross-shore sediment transport in the swash zone, Coastal Engineering Journal (JSCE), 45 (1), 63-82

Lawrence, J. 2005. Cross-shore morphodynamics of coarse grained beaches and beach/structure interaction: Numerical modelling and large scale measurements, PhD thesis, University of Plymouth, U.K

López de San Román-Blanco, B. 2003. Dynamics of gravel and mixed, sand and gravel beaches‖, PhD Thesis, Imperial College, University of London, London, UK

López de San Román-Blanco, B., Coates, T. T., Holmes, P., Chadwick, A. J., Bradbury, A., Baldock, T. E., Pedrozo-Acuña, A., Lawrence, J., Grüne, J. 2006. Large scale experiments on gravel and mixed beaches: Experimental procedure, data documentation and initial results, Coastal Engineering, 53, 349– 362

Masselink, G. and Li, L. 2001. The role of swash infiltration in determining the beachface gradient: a numerical study, Marine Geology, 176, 139–156

McCall, R.T., Van Thiel de Vries, J.S.M., Plant, N.G, Van Dongeren, A.R., Roelvink, J.A., Thompson, D.M., Reniers, A.J.H.M. 2010. Two-dimensional time dependent hurricane overwash and erosion modeling at Santa Rosa Island, Coastal Engineering, 57, 668–683

Packwood, A. R. 1983. The influence of beach porosity on wave uprush and backwash, Coastal Engineering, 7, 29-40

Pedrozo-Acuña, A. 2005. Concerning swash on steep beaches, PhD thesis, University of Plymouth, U.K

Pedrozo-Acuña, A., Simmonds, D. J., Otta, A. K., Chadwick, A. J. 2006. On the cross-shore profile change of gravel beaches, Coastal Engineering, 53, 335 – 347

Powell, K.A. 1990. Predicting Short Term Profile response for shingle beaches, Report SR 219, HR

Wallingford, Oxfordshire, UK Reeve, D. E., Chadwick, A. J. and Fleming, C. A. 2004. Coastal Engineering Processes, Theory and Design Practice, Spon Press, London

Roelvink, J.A, Reniers, A., van Dongeren, A., van Thiel de Vries, J., McCall, R., Lescinski, J. 2009.

Modelling storm impacts on beaches, dunes and barrier islands, Coastal Engineering, 56, 1133-1152

Soulsby, R.L. 1997. Dynamics of Marine Sands, Thomas Telford, HR Wallingford, London, U.K

Tang, H.S., Keen, T.R., Khanbilvardi, R. 2009. A model-coupling framework for nearshore waves, currents, sediment transport, and seabed morphology, Communications in Nonlinear Science and Numerical Simulation, 14 2935–2947

Van Thiel de Vries, J. 2009. Dune erosion during storm surges, PhD thesis, Deltares, Netherland