Dynamic characterization of two-degreeof-freedom equipment-structure systems

A two-degree-of-freedom equipment-structure system is studied to find its intrinsic properties which are needed for analysis of more general secondary systems. Perturbation theory is used to find closed form expressions for the modal properties of the system in terms of the properties of the individual subsystems. Three important characteristics of the system are identified: tuning, interaction, and nonclassical damping. Mathematical expressions are defined for each of these characteristics and criteria are developed to measure their influences on the response of the equipment. The expressions for the modal properties and the criteria for tuning, interaction, and nonclassical damping are new results for the two-degree-of-freedom system. These results form the bases for analysis of multiply supported multi-degree-of-freedom secondary systems.