Investigation of Turbulence Effects on Torsional Divergence of Long-Span Bridges by Using Dynamic Finite-Element Method
Publication: Journal of Bridge Engineering
Volume 15, Issue 6
Abstract
Aerostatic stability of super long-span bridges is a much concerned issue during the design stage. Typical aerostatic instability is the so-called torsional divergence which may lead to abrupt structural failure. The iterative static-based FEM, which generally entails the assumption of smooth oncoming flow, has been widely used to evaluate the aerostatic stability of the bridge concerned. However, the wind in atmospheric boundary layer is naturally turbulent and the effect of turbulence on bridge torsional divergence should be therefore considered, and that is the main concern of the present study. To take into account the effects of turbulence on torsional divergence, a dynamic-based time domain finite-element (FE) procedure for predicting bridge aerostatic stability is introduced first. Then the quasi-steady wind loads expressions are presented and discussed, into which the aerodynamic torsional stiffness, which is indispensable for the evaluation of aerostatic stability, has been demonstrated to be incorporated indirectly by a frequency-domain-based approach. Finally, the aerostatic performances of the longest suspension bridge in China are investigated, of which the torsional divergence is the primary concern. Numerical results show that the torsional divergence pattern in turbulent flow differs considerably from that in smooth flow. The primary difference is, while the torsional instability in smooth flow manifests as an abrupt mounting up of the twist deformation of the main girder with the increasing of the wind velocity, that in turbulent flow manifests as an unstable stochastic vibration with large peak values. Another difference is that the wind velocity for divergence in turbulent flow is obviously lower than that in smooth wind and there does not present an obvious wind velocity threshold for divergence, which is distinguished from the torsional divergence in smooth flow characterized by a clear threshold. Based on the presented time domain FE analysis procedure, the influence of turbulence intensity and gusts spatial correlation upon torsional divergence is also investigated and shown to play an important role on the aerostatic stability.
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Acknowledgments
The work described in this paper was supported by the National Science Foundation of China (Project No. UNSPECIFIED50708036 and UNSPECIFIED50738002). The writers also wish to thank the state key laboratory of disaster reduction in civil engineering of Tongji University for providing support to this research.
References
Boonyapinyo, V., Lauhatanon, Y., and Lukkunaprasit, P. (2006). “Nonlinear aerostatic stability analysis of suspension bridges.” Eng. Struct., 28(5), 793–803.
Boonyapinyo, V., Yamada, H., and Miyata, T. (1994). “Wind-induced nonlinear lateral-torsional buckling of cable-stayed bridges.” J. Struct. Eng., 120(2), 486–506.
Bucher, C. G., and Lin, Y. K. (1988). “Effect of spanwise correlation of turbulence field on the motion stochastic stability of long span bridges.” J. Fluids Struct., 2(5), 437–451.
Bucher, C. G., and Lin, Y. K. (1990). “Effect of wind turbulence on motion stability of long span bridges.” J. Wind. Eng. Ind. Aerodyn., 36(10), 1355–1364.
Chen, X. Z., and Kareem, A. (2001). “Nonlinear response analysis of long-span bridges under turbulent winds.” J. Wind. Eng. Ind. Aerodyn., 89(14–15), 1335–1350.
Chen, X. Z., and Kareem, A. (2003). “New frontiers in aerodynamic tailoring of long span bridges: An advanced analysis framework.” J. Wind. Eng. Ind. Aerodyn., 91(12–15), 1511–1528.
Cheng, J., Jiang, J. J., Xiao, R. C., and Xiang, H. F. (2002). “Nonlinear aerostatic stability analysis of Jiang Yin suspension bridge.” Eng. Struct., 24(6), 773–781.
Cheng, J., Jiang, J. J., Xiao, R. C., and Xiang, H. F. (2003). “Series method for analyzing 3D nonlinear torsional divergence of suspension bridges.” Comput. Struct., 81(5), 299–308.
Davenport, A. G. (1962). “Buffeting of a suspension bridge by storm winds.” J. Struct. Div., 88(3), 233–268.
Davenport, A. G. (1966). “The action of wind on suspension bridges.” Proc., Int. Symp. on Suspension Bridges, LNEC, Lisbon, Portugal, 79–100.
Deodatis, G. (1996). “Simulation of ergodic multivariate stochastic processes.” J. Eng. Mech., 122(8), 778–787.
Dowell, E. H., et al. (2004). A modern course in aeroelasticity, 4th Ed., Kluwer Academic, New York.
Ge, Y. J., and Xiang, H. F. (2008). “Computational models and methods for aerodynamic flutter of long-span bridges.” J. Wind. Eng. Ind. Aerodyn., 96(10–11), 1912–1924.
Jain, A., Jones, N. P., and Scanlan, R. H. (1995). “Fully-coupled buffeting analysis of long-span bridges.” Proc., 9th Int. Conf. on Wind Engineering, Wiley Eastern Science, New Delhi, India, 962–971.
Katsuchi, H., Jones, N. P., and Scanlan, R. H. (1999). “Multimode coupled flutter and buffeting analysis of the AKASHI-KAIKYO bridge.” J. Struct. Eng., 125(1), 60–70.
Katsuchi, H., Jones, N. P., Scanlan, R. H., and Akiyama, H. (1998). “A study of mode coupling in flutter and buffeting of the Akashi-Kaikyo bridge.” Journal of Structural Mechanics and Earthquake Engineering, 15(2), 281–291.
Nakamura, Y. (1993). “Bluff-body aerodynamics and turbulence.” J. Wind. Eng. Ind. Aerodyn., 49(1–3), 65–78.
Scanlan, R. H. (1997). “Amplitude and turbulence effects on bridge flutter derivatives.” J. Struct. Eng., 123(2), 232–236.
Scanlan, R. H., and Jones, N. P. (1990). “Aeroelastic analysis of cable-stayed bridges.” J. Struct. Eng., 116(2), 279–297.
Simiu, E., and Scanlan, R. H. (1996). Wind effects on structures—An introduction to wind engineering, 3rd Ed., Wiley, New York.
Information & Authors
Information
Published In
Journal of Bridge Engineering
Volume 15 • Issue 6 • November 2010
Pages: 639 - 652
Copyright
© 2010 ASCE.
History
Received: Feb 5, 2009
Accepted: Jan 8, 2010
Published online: Jan 13, 2010
Published in print: Nov 2010
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