This paper provides a practical stochastic method by which the maximum equilibrium scour depth around vertical piles exposed to long-crested (2D) and short-crested (3D) nonlinear random waves can be derived. The approach is based on assuming the waves to be a stationary narrow-band random process, adopting the Forristall wave crest height distribution (Forristall, 2000, “Wave Crest Distributions: Observations and Second-Order Theory,” J. Phys. Oceanogr., 30, pp. 1931–1943) representing both 2D and 3D nonlinear random waves, and using the regular wave formulas for scour depth by Sumer et al. (1992, “Scour Around Vertical Pile in Waves,” J. Waterway, Port, Coastal, Ocean Eng., 114(5), pp. 599–641). An example calculation is provided. Tentative approaches to related random wave-induced scour cases are also suggested.
Issue Section:
Ocean Engineering
Keywords:
scour depth,
vertical piles,
shear stress,
long-crested waves,
short-crested waves,
nonlinear random waves,
stochastic method,
offshore wind turbine
Topics:
Waves
References
1.
Whitehouse
, R. J. S.
, 1998
, Scour at Marine Structures. A Manual for Practical Applications
, Thomas Telford
, London, UK
.2.
Sumer
, B. M.
, and Fredsøe
, J.
, 2002
, The Mechanics of Scour in the Marine Environment
, World Scientific
, Singapore
.3.
De Vos
, L.
, 2008
, “Optimisation of Scour Protection Design for Monopiles and Quantification of Wave Run-Up
,” Ph.D. thesis
, University of Gent
, Belgium
.4.
Myrhaug
, D.
, and Rue
, H.
, 2003
, “Scour Below Pipelines and Around Vertical Piles in Random Waves
,” Coastal Eng.
, 48
(4
), pp.
227
–242
.10.1016/S0378-3839(03)00029-25.
Sumer
, B. M.
, Fredsøe
, J.
, and Christiansen
, N.
, 1992
, “Scour Around Vertical Pile in Waves
,” J. Waterway, Port, Coastal, Ocean Eng.
, 114
(5
), pp.
599
–641
.10.1061/(ASCE)0733-950X(1988)114:5(599)6.
Myrhaug
, D.
, Ong
, M. C.
, Føien
, H.
, Gjengedal
, C.
, and Leira
, B. J.
, 2009
, “Scour Below Pipelines and Around Vertical Piles Due to Second-Order Random Waves Plus a Current
,” Ocean Eng.
, 36
(8
), pp.
605
–616
.10.1016/j.oceaneng.2009.02.0077.
Sumer
, B. M.
, and Fredsøe
, J.
, 2001
, “Scour Around Pile in Combined Waves and Current
,” J. Hydraul. Eng.
, 127
(5
), pp.
403
–411
.10.1061/(ASCE)0733-9429(2001)127:5(403)8.
Palmer
, D.
, 1969
, “Wave Induced Scour on the Sea Floor
,” Proceedings of the Civil Engineering in the Ocean
, ASCE
, Reston, VA
.9.
Bayram
, A.
, and Larson
, M.
, 2000
, “Analysis of Scour Due to Breaking and Non-Breaking Waves Around a Group of Vertical Piles in the Field
,” Proceedings of the International Conference on Coastal Structures '99
, I. J.
Losada
, ed., Balkema
, Rotterdam
, pp.
763
–771
.10.
Forristall
, G. Z.
, 2000
, “Wave Crest Distributions: Observations and Second-Order Theory
,” J. Phys. Oceanography
, 30
, pp.
1931
–1943
.10.1175/1520-0485(2000)030<1931:WCDOAS>2.0.CO;211.
Sumer
, B. M.
, Christiansen
, N.
, and Fredsøe
, J.
, 1992
, “Time Scale of Scour Around a Vertical Pile
,” Proceedings of the 2nd International Offshore & Polar Engineering Conference
, San Francisco, CA,
Vol.
3
., pp.
308
–315
(CDROM).12.
Carreiras
, J.
, Larroudé
, P.
, Seabra-Santos
, F.
, and Mony
, M.
, 2000
, “Wave Scour Around Piles
,” Proceedings of the 20th International Conference on Coastal Engineering
, Sydney, Australia
, ASCE, Reston, VA, Vol.
2
, pp.
1860
–1870
.13.
Myrhaug
, D.
, Holmedal
, L. E.
, Simons
, R. R.
, and MacIver
, R. D.
, 2001
, “Bottom Friction in Random Waves Plus Current Flow
,” Coastal Eng.
, 43
(2
), pp.
75
–92
.10.1016/S0378-3839(01)00007-214.
Soulsby
, R. L.
, 1997
, Dynamics of Marine Sands. A Manual for Practical Applications
, Thomas Telford
, London, UK
.15.
Catano-Lopera
, Y. A.
, and Garcia
, M. H.
, 2007
, “Geometry of Scour Hole Around, and the Influence of the Angle of Attack on the Burial of Finite Length Cylinders Under Combined Flows
,” Ocean Eng.
, 34
(5–6
), pp.
856
–869
.10.1016/j.oceaneng.2006.05.00116.
Dean
, R. G.
, and Dalrymple
, R. A.
, 1984
, Water Wave Mechanics for Engineers and Scientists
, Prentice-Hall, Inc.
, NJ.
17.
Sharma
, J. N.
, and Dean
, R. G.
, 1981
, “Second-Order Directional Seas and Associated Wave Forces
,” Soc. Pet. Eng. J.
, 21
, pp.
129
–140
.18.
Sumer
, B. M.
, and Fredsøe
, J.
, 1996
, “Scour Below Pipelines in Combined Waves and Current
,” Proceedings of the 15th OMAE Conference
, Florence, Italy
, Vol.
5
, pp.
595
–602
.19.
Myrhaug
, D.
, Rue
, H.
, and Tørum
, A.
, 2004
, “Tentative Engineering Approach to Scour Around Breakwaters in Random Waves
,” Coastal Eng.
, 51
(10
), pp.
1051
–1065
.10.1016/j.coastaleng.2004.07.02220.
Myrhaug
, D.
, and Ong
, M. C.
, 2009
, “Random Wave-Induced Scour at the Trunk Section of a Breakwater
,” Coastal Eng.
, 56
(5-6
), pp.
688
–692
.10.1016/j.coastaleng.2009.01.00321.
Myrhaug
, D.
, and Rue
, H.
, 2005
, “Scour Around Groups of Slender Vertical Piles in Random Waves
,” Appl. Ocean Res.
, 27
(1
), pp.
56
–63
.10.1016/j.apor.2005.06.00122.
Myrhaug
, D.
, Føien
, H.
, and Rue
, H.
, 2007
, “Tentative Engineering Approach to Scour Around Spherical Bodies in Random Waves
,” Appl. Ocean Res.
, 29
, pp.
80
–85
.10.1016/j.apor.2007.04.00123.
Myrhaug
, D.
, Ong
, M. C.
, and Gjengedal
, C.
, 2008
, “Scour Below Marine Pipelines in Shoaling Conditions for Random Waves
,” Coastal Eng.
, 55
(12
), pp.
1219
–1223
.10.1016/j.coastaleng.2008.03.00624.
Myrhaug
, D.
, and Ong
, M. C.
, 2009
, “Burial and Scour of Short Cylinders Under Combined Random Waves and Currents Including Effects of Second Order Wave Asymmetry
,” Coastal Eng.
, 56
(1
), pp.
73
–81
.10.1016/j.coastaleng.2008.07.00625.
Myrhaug
, D.
, and Ong
, M. C.
, 2010
, “Random Wave-Induced Onshore Scour Characteristics Around Submerged Breakwaters Using a Stochastic Method
,” Ocean Eng.
, 37
(13
), pp.
1233
–1238
.10.1016/j.oceaneng.2010.04.00826.
Lillycrop
, W. J.
, and Hughes
, S. A.
, 1993
, “Scour Hole Problems Experienced by the Corps of Engineers; Data Presentation and Summary. Miscellaneous Papers
,” US Army Engineer Waterways Experiment Station Coastal Engineering Research Center
, Vicksburg, MS
, Paper No. CERC-93-2
.27.
Sumer
, B. M.
, Fredsøe
, J.
, Lamberti
, A.
, Zanuttigh
, B.
, Dixen
, M.
, Gislason
, K.
, and Di Penta
, A. F.
, 2005
, “Local Scour at Roundhead and Along the Trunk of Low Crested Structures
,” Coastal Eng.
, 52
(10-11
), pp.
995
–1025
.10.1016/j.coastaleng.2005.09.01228.
Testik
, F. Y.
, Voropayev
, S. I.
, Fernando
, H. J. S.
, and Balasubramanian
, S.
, 2007
, “Mine Burial in the Shoaling Zone: Scaling of Laboratory Results to Oceanic Situations
,” IEEE. J. Oceanic Eng.
, 32
(1
), pp.
204
–213
.10.1109/JOE.2007.89097029.
Myrhaug
, D.
, and Holmedal
, L. E.
, 2011
, “Bottom Friction and Erosion Beneath Long-Crested and Short-Crested Nonlinear Random Waves
,” Ocean Eng.
, 38
(17–18
), pp.
2015
–2022
.10.1016/j.oceaneng.2011.09.01630.
Sumer
, B. M.
, Christiansen
, N.
, and Fredsøe
, J.
, 1993
, “Influence of Cross-Section on Wave Scour Around Piles
,” J. Waterway, Port, Coastal, Ocean Eng.
, 119
(5
), pp.
477
–495
.10.1061/(ASCE)0733-950X(1993)119:5(477)31.
Sumer
, B. M.
, and Fredsøe
, J.
, 1998
, “Wave Scour Around Group of Vertical Piles
,” J. Waterway, Port, Coastal, Ocean Eng.
, 124
(5
), pp.
248
–255
.10.1061/(ASCE)0733-950X(1998)124:5(248)32.
Abramowitz
, M.
, and Stegun
, I. A.
, 1972
, Handbook of Mathematical Functions
, Dover
, New York
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