Response variability of linear stochastic systems: A general solution using random matrix theory

Adhikari, S.
49th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics & Materials Conference,Schaumburg, IL, USA, April 2008.

Uncertainties need to be taken into account for credible predictions of the dynamic response of complex structural systems. Such uncertainties should include uncertainties in the system parameters and those arising due to the modelling of a complex system. In spite of extensive research over the past four decades a general purpose probabilistic predictive code for real-life structural dynamical systems is still not available. The reasons behind this include: (a) the computational time can be prohibitively high compared to a deterministic analysis, and (b) the detailed and complete information regarding parametric and model uncertainties are in general not available. In this paper a Wishart random matrix based approach is proposed to address the above two issues. Closed-form approximate analytical expressions are developed to obtain the mean and covariance of the amplitude of the frequency response function. The method utilizes analytical inversion of the random dynamic stiffness matrix in the frequency domain. The method is applied to vibration of a cantilever plate with uncertainties. The dynamic response obtained using the Wishart random matrix model agree well with the results obtained from the stochastic finite element method.
BiBTeX Entry
@INPROCEEDINGS{cp44,
    AUTHOR={S. Adhikari},
    TITLE={Response variability of linear stochastic systems: \uppercase{a} general solution using random matrix theory},
    BOOKTITLE={49th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics \& Materials Conference},
    YEAR={2008},
    Address={Schaumburg, IL, USA},
    Month={April},
    Organization={AIAA},
    Note={}
}

by Sondipon Adhikari