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Aero-elastic wind tunnel test of a high lighting pole

  • Luo, Yaozhi (College of Civil Engineering and Architecture, Zhejiang University) ;
  • Wang, Yucheng (College of Civil Engineering and Architecture, Zhejiang University) ;
  • Xie, Jiming (College of Civil Engineering and Architecture, Zhejiang University) ;
  • Yang, Chao (College of Civil Engineering and Architecture, Zhejiang University) ;
  • Zheng, Yanfeng (College of Civil Engineering and Architecture, Zhejiang University)
  • Received : 2016.12.17
  • Accepted : 2017.06.29
  • Published : 2017.07.25

Abstract

This paper presents a 1:25 multi-freedom aero-elastic model for a high lighting pole at the Zhoushan stadium. To validate the similarity characteristics of the model, a free vibration test was performed before the formal test. Beat phenomenon was found and eliminated by synthesis of vibration in the X and Y directions, and the damping ratio of the model was identified by the free decay method. The dynamic characteristics of the model were examined and compared with the real structure; the similarity results were favorable. From the test results, the major along-wind dynamic response was the first vibration component. The along-wind wind vibration coefficient was calculated by the China code and Eurocode. When the peak factor equaled 3.5, the coefficient calculated by the China code was close to the experimental result while Eurocode had a slight overestimation of the coefficient. The wind vibration coefficient during typhoon flow was analyzed, and a magnification factor was suggested in typhoon-prone areas. By analyzing the power spectrum of the dynamic cross-wind base shear force, it was found that a second-order vortex-excited resonance existed. The cross-wind response in the test was smaller than Eurocode estimation. The aerodynamic damping ratio was calculated by random decrement technique and the results showed that aerodynamic damping ratios were mostly positive at the design wind speed, which means that the wind-induced galloping phenomenon is predicted not to occur at design wind speeds.

Keywords

References

  1. ASME (2006), Steel Stacks, The American Society of Mechanical Engineers, New York.
  2. Belloli, M., Rosa, L. and Zasso, A. (2014), "Wind loads on a high slender tower: numerical and experimental comparison", Eng. Struct., 68, 24-32. https://doi.org/10.1016/j.engstruct.2014.02.030
  3. Belver, A.V., Iban, A.L. and Lavin Martin, C.E. (2012), "Coupling between structural and fluid dynamic problems applied to vortex shedding in a 90m steel chimney", J. Wind Eng. Ind. Aerod., 100(1), 30-37. https://doi.org/10.1016/j.jweia.2011.10.007
  4. CABR (2012), Load Code for the Design of Building Structures, China Academy And Building Research, Beijing.
  5. Caracoglia, L. (2007), "Influence of weather conditions and eccentric aerodynamic loading on the large amplitude aeroelastic vibration of highway tubular poles", Eng. Struct., 29(12), 3550-3566. https://doi.org/10.1016/j.engstruct.2007.08.010
  6. Caracoglia, L. and Jones, N.P. (2007), "Numerical and experimental study of vibration mitigation for highway light poles", Eng. Struct., 29(5), 821-831. https://doi.org/10.1016/j.engstruct.2006.06.023
  7. Caracoglia, L. and Velazquez, A. (2008), "Experimental comparison of the dynamic performance for steel, aluminum and glass-fiber-reinforced-polymer light poles", Eng. Struct., 30(4), 1113-1123. https://doi.org/10.1016/j.engstruct.2007.07.024
  8. Chen, X., Li, A., Wang, Y. and Zhang, Z. (2014), "Comparative study on equivelent wind loads and dynamic responses of self-standing high-rise structures in different codes", J. Build. Struct., 4, 304-311.
  9. Eurocode (2006), Design of Steel Structures: Part 3-2: Towers, Masts and Chimneys, European Committee for Standardization, Brussels, Belgium.
  10. Fediw, A.A., Nakayama, M., Cooper, K.R., Sasaki, Y., Resende-Ide, S. and Zan, S.J. (1995), "Wind tunnel study of an oscillating tall building", J. Wind Eng. Ind. Aerod., 57(2), 249-260. https://doi.org/10.1016/0167-6105(95)00002-9
  11. Gorski, P. (2009), "Some aspects of the dynamic cross-wind response of tall industrial chimney", Wind Struct., 12(3), 259-279. https://doi.org/10.12989/was.2009.12.3.259
  12. Gu, M. and Quan, Y. (2004), "Across-wind loads of typical tall buildings", J. Wind Eng. Ind. Aerod., 92(13), 1147-1165. https://doi.org/10.1016/j.jweia.2004.06.004
  13. Ibrahim, S.R. (1977), "Random decrement technique for modal identification of structures", J. Spacecraft Rockets., 14(11), 696-700. https://doi.org/10.2514/3.57251
  14. Kawecki, J. and Zuranski, J.A. (2007), "Cross-wind vibrations of steel chimneys-a new case history", J. Wind Eng. Ind. Aerod., 95(9-11), 1166-1175. https://doi.org/10.1016/j.jweia.2007.02.001
  15. Marukawa, H., Kato, N., Fujii, K. and Tamura, Y. (1996), "Experimental evaluation of aerodynamic damping of tall buildings", J. Wind Eng. Ind. Aerod, 59(2-3), 177-190. https://doi.org/10.1016/0167-6105(96)00006-2
  16. Nguyen, C.H., Freda, A., Solari, G. and Tubino, F. (2015), "Aeroelastic instability and wind-excited response of complex lighting poles and antenna masts", Eng. Struct., 85, 264-276. https://doi.org/10.1016/j.engstruct.2014.12.015
  17. Nguyen, C.H., Freda, A., Solari, G. and Tubino, F. (2015), "Experimental investigation of the aeroelastic behavior of a complex prismatic element", Wind Struct., 20(5), 683-699. https://doi.org/10.12989/was.2015.20.5.683
  18. Pagnini, L.C. and Solari, G. (2001), "Damping measurements of steel poles and tubular towers", Eng. Struct., 23(9), 1085-1095. https://doi.org/10.1016/S0141-0296(01)00011-6
  19. Repetto, M.P. and Solari, G. (2010), "Wind-induced fatigue collapse of real slender structures", Eng. Struct., 32(12), 3888-3898. https://doi.org/10.1016/j.engstruct.2010.09.002
  20. Rosa, L., Tomasini, G., Zasso, A. and Aly, A.M. (2012), "Wind-induced dynamics and loads in a prismatic slender building: A modal approach based on unsteady pressure measurements", J. Wind Eng. Ind. Aerod., 107-108, 118-130. https://doi.org/10.1016/j.jweia.2012.03.034
  21. Sharma, R.N. and Richards, P.J. (1999), "A re-examination of the characteristics of tropical cyclone winds", J. Wind Eng. Ind. Aerod., 83(1-3), 21-33. https://doi.org/10.1016/S0167-6105(99)00058-6
  22. Simiu, E. and Scanlan, R.H. (1996), Wind Effects on Structures, Wiley
  23. Solari, G. and Pagnini, L.C. (1999), "Gust buffeting and aeroelastic behaviour of poles and monotubular towers", J. Fluids Struct.
  24. Tamura, Y. and Suganuma, S. (1996), "Evaluation of amplitude-dependent damping and natural frequency of buildings during strong winds", J. Wind Eng. Ind. Aerod., 59(2-3), 115-130. https://doi.org/10.1016/0167-6105(96)00003-7
  25. Verboom, G.K. and Van Koten, H. (2010), "Vortex excitation: three design rules tested on 13 industrial chimneys", J. Wind Eng. Ind. Aerod., 98(3), 145-154. https://doi.org/10.1016/j.jweia.2009.10.008
  26. Zhou, Y., Kijewski, T. and Kareem, A. (2002), "Along-wind load effects on tall buildings: comparative study of major international codes and standards", J. Struct. Eng. - ASCE, 128(6), 788-796. https://doi.org/10.1061/(ASCE)0733-9445(2002)128:6(788)