Application of the Probabilistic Dynamic Synthesis Method to Realistic Structures

Theprobabilisticdynamicsynthesis (PDS)method isatechniqueforobtainingthestatisticsofa desiredresponse engineering quantity for a structure with nondeterministic parameters. The method uses measured data from modal testing of the structure as the input random variables, rather than more primitive quantities like geometry ormaterial variation. Thismodalinformationismuchmorecomprehensiveandeasilymeasuredthan theprimitive information. The probabilistic analysis is carried out using either response surface reliability methods or Monte Carlo simulation. In previous work the feasibility of the PDS method applied to a simple seven-degree-of-freedom spring-mass system was verie ed. In this paper extensive issues involved with applying the method to a realistic three-substructure system are examined, and free- and forced-response analyses are performed. The results from using the method are promising, especially when the lack of alternatives for obtaining quantitative output for probabilistic structures is considered.