International Journal of Steel Structures

, Volume 18, Issue 4, pp 1318–1324 | Cite as

Ultimate Strength of 10 MW Wind Turbine Tower Considering Opening, Stiffener, and Initial Imperfection

  • Ralph Raymond Santos
  • Sung-Jun Cho
  • Jong-Sup ParkEmail author


This paper evaluates the effects of door opening, collar stiffener, and initial imperfection on the ultimate strength of a 10 MW wind tower. The lower segment of the tower was modeled to investigate the ultimate strength using steel cylindrical shell elements of finite element program ABAQUS. The wind tower was classified into three categories; without opening nor stiffener (C1), with opening but no stiffener (C2), and with opening and stiffener (C3). The C2 and C3 were further divided into long axis and short axis categories depending on the position of the opening. Result from linear and nonlinear analyses shows that the bigger the opening the bigger the reduction in strength and the same thing goes for the initial imperfection ratio or ovality of the shell. Also, there is a significant decreased in strength as the initial imperfection ratio increases by as high as 18.08%.


Wind tower Opening Stiffeners Ovality of shells Finite element analysis 



This study is funded by Ministry of Land, Transportation and Maritime Affairs of the Korean Government through the Construction Technology Innovation Program (Grant Code 12 Technology Innovation E09) and Technology Advancement Research Program (17CTAP-C132629-01).


  1. British Standards Institution. (2007). BS EN 1993-1-6:2007: Eurocode 3: Design of Steel Structures—Part 1-6: Strength and Stability of Shell Structures. London: BSI.Google Scholar
  2. Brush, D., & Almroth, B. (1975). Buckling of bars, plates, and shells. New York: McGraw-Hill.zbMATHGoogle Scholar
  3. Det Norske Veritas, A. S. (2013). DNV-RP-C208: Determination of structural capacity by non-linear finite element analysis methods. Oslo: Det Norske Veritas.Google Scholar
  4. Dimopoulos, C. A., & Gantes, C. J. (2012). Experimental investigation of buckling of wind turbine tower cylindrical shells with opening and stiffening under bending. Thin-Walled Structures, Elsevier Science Limited, 54, 140–155.CrossRefGoogle Scholar
  5. Dimopoulos, C. A., & Gantes, C. J. (2013). Comparison of stiffening types of the cutout in tubular wind turbine towers. Journal of Constructional Steel Research, Elsevier Science Limited, 83, 62–74.CrossRefGoogle Scholar
  6. Dnv, G. L. A. S. (2017). DNVGL-RP-C202: Buckling strength of shells. Oslo: DNV GL.Google Scholar
  7. Fereidoon, A., Kolasangiani, K., Akbarpour, A., & Shariati, M. (2013). Study on buckling of steel cylindrical shells with an elliptical cutout under combined loading. Journal of Computational and Applied Research in Mechanical Engineering, 3(1), 13–25.Google Scholar
  8. Germanischer Lloyd Renewables Certification. (2012). Guideline for the Certification of Offshore Wind Turbine. Hamburg: GL Renewables Certification.Google Scholar
  9. Jang, M. S., Park, J. S., Lee, Y. W., Kang, S. Y., & Kang, Y. J. (2015). A study of the effect of imperfection on buckling strength in thin cylindrical shells under bending. Journal of Korea Academia-Industrial Cooperation Society, 16(3), 2263–2271.CrossRefGoogle Scholar
  10. Kougias, L. (2009). A study of the effect of imperfections on buckling capability in thin cylindrical shells under axial loading. Master Thesis, Rensselaer Polytechnic Institute: Hartford.Google Scholar
  11. Lancaster, E. R., Calladine, C. R., & Palmer, S. C. (2000). Paradoxical buckling behaviour of a thin cylindrical shell under axial compression. International Journal of Mechanical Sciences, Elsevier Science Limited, 42(5), 843–865.CrossRefGoogle Scholar
  12. Reyno, H. (2016). The ultimate strength for the lower segment of tubular steel wind tower with opening. Master Thesis, Sangmyung University: South Korea.Google Scholar
  13. Reyno, H., Park, J. S., & Kang, Y. J. (2015). Influence of door opening and collar stiffener on the buckling capacity of cylindrical wind tower. Indian Journal of Science and Technology, 8(25), 1–7.CrossRefGoogle Scholar
  14. Shariati, M., & Rokhi, M. (2010). Buckling of steel cylindrical shells with an elliptical cutout. International Journal of Steel Structures, 10(2), 193–205.CrossRefGoogle Scholar
  15. Starnes, J. (1972). Effect of a slot on the buckling load of a cylindrical shell with a circular cutout. AAIA Journal, 10(2), 227–229.CrossRefGoogle Scholar
  16. Tennyson, R. (1968). The effects of unreinforced circular cutouts on the buckling of circular cylindrical shells under axial compression. Journal of Engineering for Industry, 90(4), 541–546.CrossRefGoogle Scholar
  17. Yeh, M., Lin, M., & Wu, W. (1999). Bending buckling of an elastoplastic cylindrical shell with a cutout. Engineering Structures, 21(11), 996–1005.CrossRefGoogle Scholar
  18. Young, W., Budynas, R., & Sadegh, A. (2011). Roark’s formulas for stress and strain (8th ed.). New York: McGraw-Hill.Google Scholar

Copyright information

© Korean Society of Steel Construction 2018

Authors and Affiliations

  1. 1.Department of Civil EngineeringSangmyung UniversityCheonan-siRepublic of Korea

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