Considerations in Using Bragg Reflection for Storm Erosion Protection
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 118, Issue 1
Abstract
It has been suggested that Bragg reflection, the combined coherent wave reflection from a few low‐lying shore‐parallel bars, might be used to protect a beach against storm‐wave attack. Numerical models are used to examine two issues relating to the feasibility of this concept: the degree of erosion protection provided by reflecting a portion of the incident wave energy, and the degree of wave reflection that can be generated by a bar field of varying geometry. The results show that a Bragg‐reflection bar field must reflect about one‐quarter of the incident wave energy to provide a significant measure of storm erosion protection. Bar fields with uniform spacing are capable of producing the required magnitude of wave reflection, but lack sufficient bandwidth. Bandwidth can be increased by staggering the spacings between bars, however, this produces a concurrent decrease in wave‐reflection magnitude. Bragg‐reflection bar fields appear capable of providing a limited measure of storm erosion protection along U.S. Gulf Coast and Atlantic Coast beaches, but their bandwidth may be too limited for use along Pacific Coast beaches.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Automated coastal engineering system. (1989). U.S. Army Corps of Engrs. Coastal Engrg. Res. Ctr., Vicksburg, Miss.
2.
Bagnold, R. A. (1963). “Mechanics of marine sedimentation.” The sea: Ideas and observations, Vol. 3, Interscience Publishing, New York, N.Y., 507–553.
3.
Bailard, J. A. (1981). “An energetics total load sediment transport model for a plane sloping beach.” J. Geophys. Res., 86(11), 10938–10954.
4.
Bailard, J. A. (1985). “Simple models for surfzone sediment transport.” Tech. Note Number N‐1740, Naval Civ. Engrg. Lab., Port Hueneme, Calif.
5.
Bailard, J. A., DeVries, J. W., Kirby, J. T., and Guza, R. T. (1990). “Bragg reflection breakwater: A new shore protection method?” Proc. 22nd Int. Conf. on Coastal Engrg., ASCE, New York, N.Y., 1702–1715.
6.
Bierkemeier, W. A., Kraus, N. C., Scheffner, N. W., and Knowles, S. C. (1987). “Feasibility study of quantitative erosion models for use by the Federal Emergency Management Agency in the prediction of coastal flooding.” Tech. Report Number TR‐87‐8, U.S. Army Corps of Engrs. Coastal Engrg. Res. Ctr., Vicksburg, Miss.
7.
Davies, A. G. (1980). “Some interactions between surface water waves and ripples and dunes of the seabed.” Tech. Report Number 108, Inst. of Oceanographic Sci., Taunton, U.K.
8.
Davies, A. G. (1982a). “On the interaction between surface waves and undulations on the seabed.” J. Mar. Res., 40(Jul.), 331–368.
9.
Davies, A. G. (1982b). “The reflection of wave energy by undulations on the seabed.” Dynamics of Atmospheres and Oceans, 6(4), 207–232.
10.
Davies, A. G., and Heathershaw, A. D. (1988). “Surface‐wave propagation over sinusoidally varying topography.” J. Fluid Mech., 144, 419–443.
11.
DeVries, J. W., and Bailard, J. A. (1989). “A simple beach profile response model.” Proc. Symp. on Mathematical Modelling of Sediment Transport in the Surfzone, Int. Association of Hydr. Res. (IAHR), Delft, The Netherlands, 215–224.
12.
Hara, T., and Mei, C. C. (1987). “Bragg scattering of surface waves by periodic bars: Theory and experiment.” J. Fluid Mech., 178(May), 59–76.
13.
Heathershaw, A. D. (1982). “Seabed‐wave resonance and sand bar growth.” Nature, 296(25), 343–345.
14.
Jensen, R. E. (1983). “Atlantic Coast hindcast, shallow‐water significant wave information.” WIS Report Number 9, U.S. Army Corps of Engrs., Waterways Experiment Station, Vicksburg, Miss.
15.
Kirby, J. T. (1986). “A general wave equation for waves over rippled beds.” J. Fluid Mech., 162(Jan.), 171–186.
16.
Kirby, J. T. (1987). “A program for calculating the reflectivity of beach profiles.” Contract Report Number UFLICOEL‐87/004, Univ. of Florida, Gainesville, Fla.
17.
Kirby, J. T., and Anton, J. P. (1990). “Bragg reflection of waves by artificial bars.” Proc. 22nd Int. Conf. on Coastal Engrg., ASCE, New York, N.Y., 757–768.
18.
Kriebel, D. L. (1982). “Beach and dune response to hurricanes,” thesis presented to Univ. of Delaware, Newark, Del., in partial fulfillment of the requirements for the degree of Master of Science.
19.
Kriebel, D. L., (1986). “Verification study of a dune erosion model.” Shore and Beach, 54(3), 13–21.
20.
Mei, C. C. (1985). “Resonant reflection of surface waves by periodic sandbars.” J. Fluid Mech., 152(Mar.), 315–335.
21.
Mei, C. C., Hara, T., and Naciri, M. (1988). “Note on Bragg scattering of water waves by parallel bars on the seabed.” J. Fluid Mech., 186(Jan.), 147–162.
22.
Thompson, E. F. (1977). “Wave climate at selected locations along U.S. coasts.” Tech. Report Number 77‐1, U.S. Army Corps of Engrs., Coastal Engrg. Res. Ctr., Vicksburg, Miss.
Information & Authors
Information
Published In
Copyright
Copyright © 1992 ASCE.
History
Published online: Jan 1, 1992
Published in print: Jan 1992
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.