Journal of Theoretical
and Applied Mechanics

50, 1, pp. 61-83, Warsaw 2012

Moment Lyapunov exponents and stochastic stability of a thin-walled beam subjected to eccentric axial loads

Goran Janevski, Predrag Kozić, Ratko Pavlović
The Lyapunov exponent and moment Lyapunov exponents of two degrees-of-freedom linear systems subjected to white noise parametric excitation are investigated. The method of regular perturbation is used to determine the explicit asymptotic expressions for these exponents in the presence of small intensity noises. The Lyapunov exponent and moment Lyapunov exponents are important characteristics for determining the almost-sure and moment stability of a stochastic dynamic system. As an example, we study the almost-sure and moment stability of a thin-walled beam subjected to an eccentric stochastic axial load. The validity of the approximate results for moment Lyapunov exponents is checked by the numerical Monte Carlo simulation method for this stochastic system.
Keywords: eigenvalues; perturbation; stochastic stability; thin-walled beam; mechanics of solids and structures