Wind and Structures

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

The nose-up effect in twin-box bridge deck flutter: Experimental observations and theoretical model

  • Ronne, Maja (Department of Bridges International, COWI) ;
  • Larsen, Allan (Department of Bridges International, COWI) ;
  • Walther, Jens H. (Department of Mechanical Engineering, Technical University of Denmark (DTU))
  • Received : 2020.10.23
  • Accepted : 2021.03.27
  • Published : 2021.04.25
⟨ Previous Next ⟩

Abstract

For the past three decades a significant amount of research has been conducted on bridge flutter. Wind tunnel tests for a 2000 m class twin-box suspension bridge have revealed that a twin-box deck carrying 4 m tall 50% open area ratio wind screens at the deck edges achieved higher critical wind speeds for onset of flutter than a similar deck without wind screens. A result at odds with the well-known behavior for the mono-box deck. The wind tunnel tests also revealed that the critical flutter wind speed increased if the bridge deck assumed a nose-up twist relative to horizontal when exposed to high wind speeds - a phenomenon termed the "nose-up" effect. Static wind tunnel tests of this twin-box cross section revealed a positive moment coefficient at 0° angle of attack as well as a positive moment slope, ensuring that the elastically supported deck would always meet the mean wind flow at ever increasing mean angles of attack for increasing wind speeds. The aerodynamic action of the wind screens on the twin-box bridge girder is believed to create the observed nose-up aerodynamic moment at 0° angle of attack. The present paper reviews the findings of the wind tunnel tests with a view to gain physical insight into the "nose-up" effect and to establish a theoretical model based on numerical simulations allowing flutter predictions for the twin-box bridge girder.

Keywords

References

  1. Abbas, T., Kavrakov, I. and Morgenthal, G. (2017), "Methods for flutter stability analysis of long-span bridges: a review", Proceedings of the Institution of Civil Engineers-Bridge Engineering, 170(4), 271-310. https://doi.org/10.1680/jbren.15.00039
  2. Chen, WL., LI, H. and Hu, H. (2014), "An experimental study on the unsteady vortices and turbulent flow structures around twin-box-girder bridge deck models with different gap ratios", J. Wind Eng. Ind. Aerod., 132(2014), 27-36. https://doi.org/10.1016/j.jweia.2014.06.015
  3. Chen, X., Kareem, A. and Matsunoto, M. (2001), "Multimode coupled flutter and buffeting analysis of long span bridges", J. Wind Eng. Ind. Aerod., 89(2001), 649-664. https://doi.org/10.1016/S0167-6105(01)00064-2
  4. D'Asdia, P. and Sepe, V. (1998), "Aeroelastic instability of long-span suspension bridges: a multi-mode approach", J. Wind Eng. Ind. Aerod., 74-76(1998), 849-857. https://doi.org/10.1016/S0167-6105(98)00077-4
  5. de Miranda, S., Patruno, L., Ricci, M. and Ubertini, F. (2015), "Numerical study of a twin box bridge deck with increasing gap ratio by using RANS and LES approaches", Eng. Struct., 99(2015), 546-558. https://doi.org/10.1016/j.engstruct.2015.05.017
  6. Diana, G., Resta, F., Zasso, A., Belloli, M. and Rocchi, D. (2004), "Forced motion and free motion aeroelastic test on a new concept dynamometric section model of the Messina suspension bridge", J. Wind Eng. Ind. Aerod.92(6), 441-462. https://doi.org/10.1016/j.jweia.2004.01.005
  7. Dyrbye, C. and Hansen, S.O. (1997), Wind Loads On Structures, John Wikey & Sons Ltd., West Sussex, England.
  8. Jain, A., Jones, N.P. and Scanlan, R.H. (1996), "Coupled aeroelastic and aerodynamic response analysis of longspan bridges", J. Wind Eng. Ind. Aerod., 60(1996), 69-80. https://doi.org/10.1016/0167-6105(96)00024-4
  9. Kong, L. and King, J.P.C. (2018), BLWT-C142-IR1-2018-V3, The Boundary Layer Wind Tunnel Laboratory, The University of Western Ontario, Faculty of Engineering, Canada. (Commercial restricted distribution).
  10. Kwok, K.C.S., Qin, X.R., Fok, C.H. and Hitchcock, P.A. (2012), "Wind-induced pressures around a sectional twin-deck bridge model: Effects on gap-width on the aerodynamic forces and vortex shedding mechanisms", J. Wind Eng. Ind. Aerod., 110(2012), 50-61. https://doi.org/10.1016/j.jweia.2012.07.010
  11. Larsen, A. and Astiz, M.A. (1998), "Aeroelastic considerations for the Gibraltar Bridge feasibility study", International Symposium on Advances in Bridge Aerodynamics, Copenhagen, Denmark, May.
  12. Larsen, A. and Walther, J.H. (1997), "Aeroelastic analysis of bridge girder sections based on discrete vortex simulations", J. Wind Eng. Ind. Aerod., 67(8), 253-265. https://doi.org/10.1016/S0167-6105(97)00077-9.
  13. Larsen, A. and Walther, J.H. (1998), "Discrete vortex simulation of flow around five generic bridge deck sections", J. Wind Eng. Ind. Aerod., 77(8), 591-602. https://doi.org/10.1016/S0167-6105(98)00175-5.
  14. Larsen, A. (1993), "Aerodynamic aspects of the final design of the 1624 m suspension bridge across the Great Belt", J. Wind Eng. Ind. Aerod., 48(3), 261-285. https://doi.org/10.1016/0167-6105(93)90141-A
  15. Larsen, A. (2016a), "The role of horizontal aerodynamic derivatives in bridge flutter analysis", First International Symposium on Flutter and its Application. Tokyo, Japan, May.
  16. Larsen, A. (2016b), Bridge Deck Flutter Analysis. Proceedings of the Danish Society for Structural Science and Engineering, June. (https://www.dsby.dk/media/dsbypdf/2016/BSM-86-nr%202-4.pdf)
  17. Mannini, C. and Bartoli, G. (2008), "Investigation on the dependence of bridge deck flutter derivatives on the steady angle of attack", BBAA VI: International Colloquium on Bluff Bordies Aerodynamics & Applications, Milano, Italy, July.
  18. Ogawa, K., Shimodoi, H. and Oryu, T. (2002), "Aerodynamic characteristics of a 2-box grider section adaptable for a super-long span suspension bridge", J. Wind Eng. Ind. Aerod., 90(12-15), 2033-2043. https://doi.org/10.1016/S0167-6105(02)00319-7
  19. Richardson, J.R. (1981), "The development of the concept of the twin suspension bridge", Report No. NMI R125; National Maritime Institute, Feltham, United Kingdom.
  20. Sato, H., Hirahara, N., Fumoto, K., Hirano, S. and Kusuhara, S. (2002), "Full aeroelastic model test of a long-span bridge with slotted box girder", J. Wind Eng. Ind. Aerod., 90(12-15), 2023-2032. https://doi.org/10.1016/S0167-6105(02)00318-5.
  21. Scanlan, R.H. and Rosenbaum, R. (1962), Introduction to the Study of Aircraft Vibration and Flutter, The MacMillan Company, New York, New York, U.S.A.
  22. Scanlan, R.H. and Tomko, J.J. (1971), "Airfoil and Bridge Deck Flutter Derivatives", J. Eng. Mech., ASCE (97) EM6, 1717-1737.
  23. Smilg, B. and Wassermann, L.S. (1942), "Application of three-dimensional flutter theory to aircraft structures", AAF Technical Report 4798, July.
  24. Walther, J.H. and Larsen, A. (1997), "Two dimensional discrete vortex method for application to bluff body aerodynamics", J. Wind Eng. Ind. Aerod., 67(8), 183-193. https://doi.org/10.1016/S0167-6105(97)00072-X.
  25. Yang, Y., Wu, T., Ge, Y. and Kareem, A. (2015a), "Aerodynamic stabilization mechanism of a twin box girder with various slot widths", J. Bridge Eng., 20(3), 04014067. https://doi.org/10.1016/(ASCE)BE.1943-5592.0000645
  26. Yang, Y., Zhou, R., Ge, Y., Mohotti, D. and Mendis, P. (2015b), "Aerodynamic instability performance of twin box girders for long-span bridges", J. Wind Eng. Ind. Aerod., 145(2015), 196-208. https://doi.org/10.1016/j.jweia.2015.06.014