Analysis of Bayed Beaches in Static Equilibrium
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 120, Issue 2
Abstract
A bayed beach in equilibrium could be in a state of either dynamic or static equilibrium; the latter being a special case of the former when the absolute quantity of longshore transport is nil. As a bay approaches its equilibrium shape, the net sediment‐transport rate in the bay decreases and eventually ceases. The writers carried out a series of model beach studies to investigate the planform of crenulate‐shaped bays in static equilibrium. By adopting the method of measurement proposed by Hsu and Evans in 1989, the writers found that the effects of beach materials, wave characteristics (other than wave approach), and location and spacing of breakwaters need not be considered separately. In further consideration of the tangent of the bay planform at the downcoast control point, the writers found that a second‐order polynomial equation of with as the parameter could be used to describe the crenulate‐shaped bay in static equilibrium for a wide range of wave obliquity, ; is the shortest line between the upcoast breakwater to a point on the beach, and is the angle between this line and the incident wave crests; when . This approach also leads to the simplification of the proposed equation and reduces the number of unknowns from three unknown coefficients to a single variable, , which had been determined using the results of the present study and indirect comparison with published data. A list of for a wide range of wave obliquity is also presented.
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References
1.
Dean, R. G., and Maurmeyer, E. M. (1977). “Predictability of characteristics of two embayments.” Coastal Sediments. ASCE, New York, N.Y., 848–866.
2.
Hardaway, C. S. Jr., and Gunn, J. R. (1991). “Headland breakwaters in Chesapeake Bay.” Coastal Zone '91. ASCE, New York, N.Y., Vol. 2, 1261–1281.
3.
Hsu, J. R., and Evans, C. (1989). “Parabolic bay shapes and applications.” Proc., Institution of Civil Engineers, London, England, Vol. 87 (part 2), 557–570.
4.
Hsu, J. R., Silvester, R., and Xia, Y. M. (1989). “Static equilibrium bays: new relationships.” J. Wtrwy., Port, Coast., and Oc. Engrg., ASCE, 115(3), 285–298.
5.
Krumbein, W. C. (1947). “Shore processes and beach characteristics.” Tech. Memo 3, U.S. Army Beach Erosion Board, Washington, D.C.
6.
Le Blond, P. H. (1979). “An explanation of the logarithmic spiral plan shape of headland‐bay beaches.” J. Sedimentary Petrology, 49(4), 1093–1100.
7.
Rea, C. C., and Komar, P. D. (1975). “Computer simulation of a hooked beach shoreline configuration.” J. Sedimentary Petrology, Vol. 45, 866–872.
8.
Silvester, R., and Ho, S. K. (1972). “Use of crenulate shaped bays to stabilize coasts.” Proc., 13th Conf. on Coast. Engrg., Vol. 2, ASCE, New York, N.Y., 1347–1365.
9.
Tan, S. K., and Chiew, Y. M. (1991). “Beach erosion control by using detached breakwaters.” Federal Interagency Sedimentation Conf., Las Vegas, Nev., 3.87–92.
10.
Yasso, W. E. (1965). “Plan geometry of headland bay beaches.” J. Geology, Vol. 73, 702–714.
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Copyright © 1994 American Society of Civil Engineers.
History
Received: Jul 20, 1992
Published online: Mar 1, 1994
Published in print: Mar 1994
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