New Stochastic Theory for Bridge Stability in Turbulent Flow. II
- 1 January 1995
- journal article
- Published by American Society of Civil Engineers (ASCE) in Journal of Engineering Mechanics
- Vol. 121 (1), 102-116
- https://doi.org/10.1061/(asce)0733-9399(1995)121:1(102)
Abstract
Motion stability of a long-span bridge in turbulent wind is studied. The bridge motion is represented by a torsional mode and a bending mode, and the new wind turbulence model proposed in an earlier paper is used in the analysis. This turbulence model is capable of matching closely a target spectral density, such as the well-known von-Kármán or Dryden spectrum. It is shown that the presence of turbulence changes the combined structure-fluid critical mode and results in a new energy balance. The asymptotic behavior of the combined structure-fluid system is determined by the largest Lyapunov exponent, and the motion is asymptotically stable if the largest Lyapunov exponent is negative. In this sense, the turbulence has a stabilizing or a destabilizing effect, depending on whether it increases or decreases the critical mean wind velocity at which the largest Lyapunov exponent vanishes. For a particular bridge model investigated, it is found that the peak location of the spectral density of the turbulence is crucial to the stability condition. By changing the peak location of the spectrum, a stabilizing turbulence can become destabilizing, even when the mean-square value remains the same.Keywords
This publication has 10 references indexed in Scilit:
- New Stochastic Theory for Bridge Stability in Turbulent FlowJournal of Engineering Mechanics, 1993
- Stochastic Stability of Bridges Considering Coupled Modes: IIJournal of Engineering Mechanics, 1989
- Stochastic Stability of Bridges Considering Coupled ModesJournal of Engineering Mechanics, 1988
- Application of stochastic averaging for nonlinear dynamical systems with high dampingProbabilistic Engineering Mechanics, 1988
- Stability of Bridge Motion in Turbulent WindsJournal of Structural Mechanics, 1980
- Indicial Aerodynamic Functions for Bridge DecksJournal of the Engineering Mechanics Division, 1974
- Airfoil and Bridge Deck Flutter DerivativesJournal of the Engineering Mechanics Division, 1971
- A survey of stability of stochastic systemsAutomatica, 1969
- On a Formula Concerning Stochastic DifferentialsNagoya Mathematical Journal, 1951
- Progress in the Statistical Theory of TurbulenceProceedings of the National Academy of Sciences of the United States of America, 1948