PROBABILISTIC COMPONENT MODE SYNTHESIS OF NONDETERMINISTIC SUBSTRUCTURES

Standard methods of structural dynamic analysis assume that the struct ural characteristics are deterministic. Recognizing that these charact eristics are actually statistical in nature, researchers have recently developed a variety of methods that use this information to determine probabilities of a desired response characteristic, such as natural f requency, without using expensive Monte Carlo simulations. One of the problems in these methods is correctly identifying the statistical pro perties of primitive variables such as geometry, stiffness, and mass. We present a method where the measured dynamic properties of substruct ures are used instead as the random variables. The residual flexibilit y method of component mode synthesis is combined with the probabilisti c methods to determine the cumulative distribution function of the sys tem eigenvalues. A simple cantilever beam test problem is presented th at illustrates the theory.