Ivo Van der Werf, Marcel R.A. Van Gent


This paper focusses on some fundamental aspects of gravel beaches and revetments with dynamic rock slopes. Obviously, the response of gravel beaches depends on parameters such as the wave height and the stone size. Here, other parameters such as the permeability of the subsoil, the influence of sand in the pores of gravel, and the influence of seawalls have been studied. The results from the physical model tests indicate that a homogeneous mound of gravel with an initial slope of 1:8 leads to a more dynamic response than a gravel beach with an impermeable subsoil. The results also show that if the pores are filled with sand, the response becomes less dynamic. Placing a seawall on a gravel beach may be interesting for gravel beaches that serve as (man-made) sea defence. Furthermore, the results provide insight into the magnitude of scale effects.


rock slopes; gravel beaches; cobble beaches; seawalls; dynamic revetments; wave flume; permeability

Full Text:



Kao, J.S. and K.R. Hall. 1990. Trends in stability of dynamically stable breakwaters, Proc. ICCE 1990, ASCE, Vol.2, pp.1730-1741, Delft.

Loman, G.J.A., M.R.A. van Gent and J.W. Markvoort. 2010. Physical model testing of an innovative cobble shore; Part 1: Verification of cross-shore profile deformation. In preparation for the Proc. International Coastlab Conference, Sept/Oct 2010, Barcelona.

PIANC. 2003. State-of-the-art of designing berm breakwaters. MarCom, Report of WG40, 2003, International Navigation Association.

She, K., D. Horn, P. Canning. 2007. Influence of permeability on the performance of shingle and mixed beaches. Joint Defra/EA Flood and Coastal Erosion Risk Management R&D Programme, Research Scoping Study, R&D Technical Report FD1923/TR, December 2007.

Van der Meer, J.W. 1988. Rock slopes and gravel beaches under wave attack, Ph.D. thesis Delft University of Technology, Delft.

Van Gent, M.R.A. 1995-a. Wave interaction with Berm breakwaters, J. of Waterway, Port, Coastal and Ocean Engineering, Vol.121, no.5, pp.229-238, ASCE, New York.

Van Gent, M.R.A. 1995-b. Wave interaction with permeable coastal structures, Ph.D.-thesis Delft University of Technology, ISBN 90-407-1182-8, Delft University Press, Delft.

Van Gent, M.R.A. 1996. Numerical modelling of wave interaction with dynamically stable structures, Proc. ICCE 1996, ASCE, Vol.2, pp.1930-1743, Orlando.

Van Gent, M.R.A., J.S.M. van Thiel de Vries, E.M. Coeveld, J.H. de Vroeg and J. van de Graaff. 2008. Large-scale dune erosion tests to study the influence of wave periods, Elsevier, Coastal Engineering, Vol.55, pp.1041-1051.