China Ocean Engineering

, Volume 32, Issue 6, pp 737–745 | Cite as

Experimental Investigation of Local Scour Around A New Pile-Group Foundation for Offshore Wind Turbines in Bi-Directional Current

  • Chao Ji
  • Jin-feng ZhangEmail author
  • Qing-he Zhang
  • Ming-xing Li
  • Tong-qing Chen
Technical Notes


The local scour around a new pile-group foundation of offshore wind turbine subjected to a bi-directional current was physically modeled with a bi-directional flow flume. In a series of experiments, the flow velocity and topography of the seabed were measured based on a system composed of plane positioning equipment and an ADV. Experimental results indicate that the development of the scour hole was fast at the beginning, but then the scour rate decreased until reaching equilibrium. Erosion would occur around each pile of the foundation. In most cases, the scour pits were connected in pairs and the outside widths of the scour holes were larger than the inner widths. The maximum scour depth occurred at the side pile of the foundation for each test. In addition, a preliminary investigation shows that the larger the flow velocity, the larger the scour hole dimensions but the shorter equilibrium time. The field maximum scour depth around the foundation was obtained based on the physical experiments with the geometric length scales of 1:27.0, 1:42.5 and 1:68.0, and it agrees with the scour depth estimated by the HEC-18 equation.

Key words

offshore wind turbines new pile-group foundation local scour bi-directional current 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Allen, J., 1947. Scale Models in Hydraulic Engineering, Longmans, Green, London.Google Scholar
  2. Amini, A., Melville, B.W., Ali, T.M. and Ghazali, A.H., 2012. Clearwater local scour around pile groups in shallow-water flow, Journal of Hydraulic Engineering, 138(2), 177–185.CrossRefGoogle Scholar
  3. Ataie-Ashtiani, B. and Beheshti, A.A., 2006. Experimental investigation of clear-water local scour at pile groups, Journal of Hydraulic Engineering, 132(10), 1100–1104.CrossRefGoogle Scholar
  4. Bilgili, M., Yasar, A. and Simsek, E., 2011. Offshore wind power development in Europe and its comparison with onshore counterpart, Renewable and Sustainable Energy Reviews, 15(2), 905–915.CrossRefGoogle Scholar
  5. Camenen, B. and Larson, M., 2005. A general formula for non-cohesive bed load sediment transport, Estuarine, Coastal and Shelf Science, 63(1–2), 249–260.CrossRefGoogle Scholar
  6. De Vos, L., De Rouck, J., Troch, P. and Frigaard, P., 2011. Empirical design of scour protections around monopile foundations: Part 1: Static approach, Coastal Engineering, 58(6), 540–553.CrossRefGoogle Scholar
  7. Den Boon, J.H., Sutherland, J., Whitehouse, R., Soulsby, R., Stam, C.J.M., Verhoeven, K., Høgedal, M. and Hald, T., 2004. Scour behaviour and scour protection for monopile foundations of offshore wind turbines, Proceedings of the European Wind Energy Conference, EWEC, London, UK.Google Scholar
  8. Ezzeldin, M.M., Moharram, S.H., Sarhan, T.E. and Elhamrawy, A.M.S., 2006. Scour around pile group of small bridge, Proceedings of the 10th International Water Technology Conference, IWTC, Alexandria, Egypt, pp. 985–1002.Google Scholar
  9. Han, H.Q., 2006. Research on Local Scour at Bridge Piers under Tidal Current Action, MSc. Thesis, Zhejiang University, Hangzhou. (in Chinese)Google Scholar
  10. Han, Y.F. and Chen, Z.C., 2004. Experimental study on local scour around bridge piers in tidal current, China Ocean Engineering, 18(4), 669–676.Google Scholar
  11. Hosseini, R. and Amini, A., 2015. Scour depth estimation methods around pile groups, KSCE Journal of Civil Engineering, 19(7), 2144–2156.CrossRefGoogle Scholar
  12. Jones, J.S. and Sheppard, D.M., 2000. Local scour at complex pier geometries, Proceedings of the ASCE 2000 Joint Conference on Water Resource Engineering and Water Resources Planning and Management, ASCE, Minneapolis, MN.Google Scholar
  13. Lang, R.Q., Liu, R., Lian, J.J. and Ding, H.Y., 2015. Study on loadbearing characteristics of different types of pile group foundations for an offshore wind turbine, Journal of Coastal Research, Special Issue 73–Recent Developments of Port and Ocean Engineering, 533–541.Google Scholar
  14. Lin, Y.F. and Zhou, X., 2010. Structural characteristics and design technical keys of wind turbine foundation in Shanghai Donghai-Bridge offshore wind farm, GeoShanghai International Conference 2010, ASCE, Shanghai, pp. 52–60.Google Scholar
  15. Liu, R., Chen, G.S., Lian, J.J. and Ding, H.Y., 2015a. Vertical bearing behaviour of the composite bucket shallow foundation of offshore wind turbines, Journal of Renewable and Sustainable Energy, 7(1), 013123.CrossRefGoogle Scholar
  16. Liu, R., Zhou, L., Lian, J.J. and Ding, H.Y., 2015b. Behavior of monopile foundations for offshore wind farms in sand, Journal of Waterway, Port, Coastal, and Ocean Engineering, 142(1), 04015010.CrossRefGoogle Scholar
  17. Lu, Z.Y., Gao, Z.R., Huang, J.W., Han, X. and Liu, J.J., 2005. Test comparison between tidal and unidirectional flow experiments of the partial scouring for the pier foundations, Proceedings of the 7th National Congress on Hydrodynamics and 19th National Conference on Hydrodynamics, China Society of Mechanics, China Shipbuilding Engineering Society, Harbin, pp. 974–981. (in Chinese)Google Scholar
  18. Lu, Z.Y., Gao, Z.R., Huang, J.W., Han, X. and Liu, J.J., 2011. Local scour around pier foundation of Suzhou–Nantong Yangtze River Highway Bridge, Proceedings of the 15th China Ocean (Coastal) Engineering, Chinese Society of Oceanography, Taiyuan, pp. 1300–1304. (in Chinese)Google Scholar
  19. Matutano, C., Negro, V., López-Gutiérrez, J.S. and Esteban, M.D., 2013. Scour prediction and scour protections in offshore wind farms, Renewable Energy, 57, 358–365.CrossRefGoogle Scholar
  20. Melville, B.W. and Coleman, S.E., 2000. Bridge Scour, Water Resources Publication, Colorado.Google Scholar
  21. Mostafa, Y.E. and Agamy, A.F., 2011. Scour around single pile and pile groups subjected to waves and currents, International Journal of Engineering Science and Technology, 3(11), 8160–8178.Google Scholar
  22. Nakagawa, H. and Suzuki, K., 1976. Local scour around bridge pier in tidal current, Coastal Engineering in Japan, 19, 89–100.CrossRefGoogle Scholar
  23. Petersen, T.U., Sumer, B.M., Fredsøe, J., Raaijmakers, T.C. and Schouten, J.J., 2015. Edge scour at scour protections around piles in the marine environment—laboratory and field investigation, Coastal Engineering, 106, 42–72.CrossRefGoogle Scholar
  24. Prendergast, L.J., Gavin, K. and Doherty, P., 2015. An investigation into the effect of scour on the natural frequency of an offshore wind turbine, Ocean Engineering, 101, 1–11.CrossRefGoogle Scholar
  25. Qi, W.G. and Gao, F.P., 2014. Physical modeling of local scour development around a large-diameter monopile in combined waves and current, Coastal Engineering, 83, 72–81.CrossRefGoogle Scholar
  26. Qi, W.G., Tian, J.K., Zheng, H.Y., Wang, H.Y., Yang, J., He, G.L. and Gao, F.P., 2014. Bearing capacity of the high-rise pile cap foundation for offshore wind turbines, International Conference on Sustainable Development of Critical Infrastructure, ASCE, Shanghai, pp. 413–420.CrossRefGoogle Scholar
  27. Richardson, E.V. and Davis, S.R., 2001. Evaluating Scour at Bridges 4th, Hydraulic Engineering Circular No. 18, Federal Highway Administration, Washington, D.C.Google Scholar
  28. Sha, Y.Q., 1963. Extend method of series models, Journal of Hydraulic Engineering, (5), 13–21. (in Chinese)Google Scholar
  29. Soulsby, R., 1997. Dynamics of Marine Sands: A Manual for Practical Applications, Thomas Telford Publications, London, England.Google Scholar
  30. Sumer, B.M. and Fredsøe, J., 1997. Hydrodynamics Around Cylindrical Structures, World Scientific, London.CrossRefzbMATHGoogle Scholar
  31. Sumer, B.M. and Fredsøe, J., 1998. Wave scour around group of vertical piles, Journal of Waterway, Port, Coastal, and Ocean Engineering, 124(5), 248–256.CrossRefGoogle Scholar
  32. Sumer, B.M., Fredsøe, J. and Christiansen, N., 1992. Scour around vertical pile in waves, Journal of Waterway, Port, Coastal, and Ocean Engineering, 118(1), 15–31.CrossRefGoogle Scholar
  33. Wang, Q., Huang, C.Y., Lin, G.B. and Dai, R.Y., 1989. Experimental study of scour around bridge piers under tidal current, Journal of Railway Engineering Society, (4), 24–30. (in Chinese)Google Scholar
  34. Yu, T.S., Lian, J.J., Shi, Z.Q. and Wang, H.Z., 2016. Experimental investigation of current-induced local scour around composite bucket foundation in silty sand, Ocean Engineering, 117, 311–320.CrossRefGoogle Scholar

Copyright information

© Chinese Ocean Engineering Society and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Chao Ji
    • 1
  • Jin-feng Zhang
    • 1
    Email author
  • Qing-he Zhang
    • 1
  • Ming-xing Li
    • 2
  • Tong-qing Chen
    • 1
  1. 1.State Key Laboratory of Hydraulic Engineering Simulation and SafetyTianjin UniversityTianjinChina
  2. 2.Fourth Harbor Engineering Investigation and Design Institute, Co., Ltd.China Communications Construction CompanyGuangzhouChina

Personalised recommendations