Uncertainty in Structural Dynamics: Experimental Case Studies on Beams and Plates
Adhikari, S., Friswell, M. I. and Lonkar, K.
Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2007),
Crete, Greece, June 2007.
The consideration of uncertainties in numerical models
to obtain the probabilistic descriptions of vibration response is
becoming more desirable for industrial scale finite element
models. Broadly speaking, there are two aspects to this problem.
The first is the quantification of parametric and non-parametric
uncertainties associated with the model and the second is the
propagation of uncertainties through the model. While methods of
uncertainty propagation have been extensively researched in the
past two decades (e.g., the stochastic finite element method),
only relatively recently has quantification been considered
seriously. This paper considers uncertainty quantification with
the aim of gaining more insight into the nature of uncertainties
in medium and high frequency vibration problems. Results from two
experimental studies that may be used for this purpose are
described in detail. The first experiment uses a fixed-fixed beam
with 12 masses placed at random locations. The total `random mass'
is about 2% of the total mass of the beam and this experiment
simulates `random errors' in the mass matrix. The second
experiment uses a cantilever plate with 10 randomly placed
spring-mass oscillators. This experiment simulates the problem of
`unmodelled dynamics', which in turn results in randomness in both
the mass and stiffness matrices. For both experiments, 100
nominally identical dynamical systems are created and individually
tested. The probabilistic characteristics of the frequency
response functions are discussed in the low, medium and high
frequency ranges. The data obtained in these experiments may be
useful for the validation of uncertainty quantification and
propagation methods in structural dynamics.
BiBTeX Entry
@INPROCEEDINGS{cp39,
AUTHOR={S. Adhikari and M. I. Friswell and K. Lonkar},
TITLE={Uncertainty in structural dynamics: Experimental case studies on beams and plates},
BOOKTITLE={Proceedings of the Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN)},
YEAR={2007},
Address={Crete, Greece},
Month={June},
Note={}
}
by Sondipon Adhikari