Structural Monitoring and Maintenance

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Conditions to avoid synchronization effects in lateral vibration of footbridges

  • Andrade, Alexandre R. (Unidade Academica de Controles e Processos Industriais, Instituto Federal da Paraiba, Campus Joao Pessoa) ;
  • Pimentel, Roberto L. (Departamento de Engenharia Civil e Ambiental, Universidade Federal da Paraiba) ;
  • Silva, Simplicio A. da (Departamento de Engenharia Elétrica, Universidade Federal da Paraiba) ;
  • Souto, Cicero da R. (Departamento de Engenharia Elétrica, Universidade Federal da Paraiba)
  • Received : 2020.10.09
  • Accepted : 2022.05.22
  • Published : 2022.06.25
⟨ Previous Next ⟩

Abstract

Lateral vibrations of footbridges may induce synchronization between pedestrians and structure itself, resulting in amplification of such vibrations, a phenomenon identified by lock-in. However, investigations about accelerations and frequencies of the structural movement that are related to the occurrence of synchronization are still incipient. The aim of this paper is to investigate conditions that could lead to avoidance of synchronization among pedestrians themselves and footbridge, expressed in terms of peak acceleration. The focus is on the low acceleration range, employed in some guidelines as a criterion to avoid synchronization. An experimental campaign was carried out, employing a prototype footbridge that was set into oscillatory motion through a pneumatic exciter controlled by a fuzzy system, with controlled frequency and amplitude. Test subjects were then asked to cross the oscillating structure, and accelerations were simultaneously recorded at the structure and at the subject's waist. Pattern and phase differences between these signals were analysed. The results showed that test subjects tended to keep their walking patterns without synchronization induced by the vibration of the structure, for structural peak acceleration values up to 0.18 m/s2, when frequencies of oscillation were around 0.8 to 0.9 Hz. On the other hand, for frequencies of oscillation below 0.7 Hz, structural peak accelerations up to 0.30 m/s2 did not induce synchronization.

Keywords

Acknowledgement

Financial support of Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) is fully acknowledged.

References

  1. Blekherman, A.N. (2005), "Swaying of pedestrian bridges", J. Bridge Eng., 10(2), 142-150. https://doi.org/10.1061/(ASCE)1084-0702(2005)10:2(142).
  2. Bocian, M., Macdonald, J.H.G., Burn, J.F. and Redmill, D. (2015), "Experimental identification of the behaviour of and lateral forces from freely-walking pedestrians on laterally oscillating structures in a virtual reality environment", Eng. Struct., 105, 62-76. https://doi.org/10.1016/j.engstruct.2015.09.043.
  3. Bocian, M., Burn, J.F., Macdonald, J.H.G. and Brownjohn, J.M.W. (2017), "From phase drift to synchronisation - pedestrian stepping behaviour on laterally oscillating structures and consequences for dynamic stability", J. Sound Vib., 392, 382-399. https://doi.org/10.1016/j.jsv.2016.12.022.
  4. Brownjohn, J.M.W., Fok, P., Roche, M. and Omenzetter, P. (2004), "Long span steel pedestrian bridge at Singapore Changi Airport - Part 2: Crowd loading tests and vibration mitigation measures", Struct. Eng., 82(16), 28-34.
  5. Caetano, E., Cunha, A., Magalhaes, F. and Moutinho, C. (2010), "Studies for controlling human-induced vibration of the Pedro e Ines footbridge, Portugal. Part 1: Assessment of dynamic behavior", Eng. Struct., 32, 1069-1081. https://doi.org/10.1016/j.engstruct.2009.12.034.
  6. Carroll, S.P., Owen, J.S. and Hussein, M.F.M. (2013), "Reproduction of lateral ground reaction forces from visual marker data and analysis of balance response while walking on a laterally oscillating deck", Eng. Struct., 49, 1034-1047. https://doi.org/10.1016/j.engstruct.2012.12.028.
  7. Charles, P. and Bui, V. (2005), "Transversal dynamic actions of pedestrians - Synchronization", Footbridge 2005 (Second International Congress), Venezia, Italy, December.
  8. Chen, Z., Chen, S., Ye, X. and Zhou, Y. (2019), "A study on a mechanism of lateral pedestrian-footbridge interaction", Appl. Sci., 9, 5257. https://doi.org/10.3390/app9235257.
  9. Cuevas, R.G., Jimenez-Alonso, J.F., Martinez, F. and Diaz, I.M. (2020), "Assessment of the lateral vibration serviceability limit state of slender footbridges including the postlock-in behaviour", Appl. Sci., 10, 967. https://doi.org/10.3390/app10030967.
  10. Dallard, P., Fitzpatrick, T., Flint, A., Low, A., Smith, R.R., Willford, M. and Roche, M. (2001), "London Millennium Bridge: pedestrian-induced lateral vibration", J. Bridge Eng., 6(6), 412-417. https://doi.org/10.1061/(ASCE)1084-0702(2001)6:6(412).
  11. Danbon, F. and Grillaud, G. (2005), "Dynamic behavior of a steel footbridge. Characterisation and modeling of the dynamic loading induced by a moving crowd on the Solferino footbridge in Paris", Footbridge 2005 (Second International Congress), Venezia, Italy, December.
  12. Fujino, Y., Pacheco, B.M., Nakamura, S. and Warnitchai, P. (1993), "Synchronization of human walking observed during lateral vibration of a congested pedestrian bridge", Earthq. Eng. Struct. Dyn., 22(9), 741-758. https://doi.org/10.1002/eqe.4290220902.
  13. Hivoss - Human Induced Vibrations of Steel Structures, (2008a), Design of Footbridges Background Document, Research Fund for Coal & Steel, European Commission.
  14. Hivoss - Human Induced Vibrations of Steel Structures, (2008b), Design of Footbridges Guideline, Research Fund for Coal & Steel, European Commission.
  15. Ingolfsson, E.T., Georgakis, C.T., Richiardelli, F. and Procino, L. (2010), "Lateral human-structure intereaction on footbridge", 10th International Conference on Recent Advances in Structural Dynamics, Southampton, UK, July.
  16. Jia, B., Yu, X., Yan, Q., Yang, Z. and Chen, Y. (2020), "Stability analysis of pedestrian-induced large lateral vibration on a footbridge", Struct. Infrastr. Eng., 17(3), 291-301. https://doi.org/10.1080/15732479.2020.1739720.
  17. Jia, B., Yu, X. and Yan, Q. (2018), "Effects of stochastic excitation and phase lag of pedestrians on lateral vibration of footbridges", Int. J. Struct. Stab. Dyn., 18(7), 1850095. https://doi.org/10.1142/S0219455418500955.
  18. Jimenez-Alonso, J.F., Saez, A., Caetano, E. and Cunha, A. (2019), "Lateral crowd-structure interaction model to analyse the change of the modal properties of footbridges", Struct. Control Hlth. Monit., 26, e2356. https://doi.org/10.1002/stc2356.
  19. Macdonald, J.H.G. (2008), "Pedestrian-induced vibrations of the Clifton Suspension Bridge, UK", Proc. Inst. Civil Eng.-Bridge Eng., 161(2), 69-77. https://doi.org/10.1680/bren.2008.161.2.69.
  20. Nakamura, S. (2003), "Field measurements of lateral vibration on a pedestrian suspension bridge", Struct. Eng., 81(22), 22-26.
  21. Nakamura, S. and Kawasaki, T. (2006), "Lateral vibration of footbridges by synchronous walking", J. Constr. Steel Res., 62(11), 1148-1160. https://doi.org/10.1016/j.jcsr.2006.06.023.
  22. Pizzimenti, A.D. and Ricciardelli, F. (2005), "Experimental evaluation of the dynamic lateral loading of footbridges by walking pedestrians", Sixth European Conference on Structural Dynamics EURODYN, Paris, France, September.
  23. Ronnquist, A., Strommen, E. and Wollebaek, L. (2008), "Dynamic properties from full scale recordings and FE-modelling of a slender footbridge with flexible connections", Struct. Eng. Int., 18(4), 421-426. https://doi.org/10.2749/101686608786455162.
  24. Setra - Service d'Etudes Techniques des Routes et Autoroutes, (2006), "Technical guide Footbridges - Assessment of vibrational behaviour of footbridges under pedestrian loading", Association Francaise de Genie Civil, Paris, France.
  25. Silva, F.T., Brito, H.M.B.F. and Pimentel, R.L. (2013), "Modeling of crowd load in vertical direction using biodynamic model for pedestrians crossing footbridges", Can. J. Civil Eng., 40(12), 1196-1204. https://doi.org/10.1139/cjce-2011-0587.
  26. Sun, L. and Yuan, X. (2008), "Study on pedestrian-induced vibration of footbridge", Proceedings of the Third International Conference Footbridge 2008, Porto, Portugal, July.
  27. Yoshida, J., Fujino, Y. and Sugiyama, T. (2007), "Image processing for capturing motions of crowd and its application to pedestrian-induced lateral vibration of a footbridge", Shock Vib., 14(4), 251-260. https://doi.org/10.1155/2007/763437