A Dynamic-Test Procedure for Improving Seismic Qualification Guidelines

Several shortcomings of available standards, regulatory guides, and review plans for seismic qualification testing are identified. A rational test nomenclature is proposed. A standard test is developed by optimizing an appropriate test severity measure function. The standard test is a rectilinear test that is equivalent to the three-degree-of-freedom test with uncorrelated excitations, recommended in IEEE-Std. 344. In terms of eigenvectors of a resulting test matrix, a dynamic interpretation is given for principal axes of a test object. The proposed approach to dynamic testing has two main advantages in comparison to the conventional approach of black-box testing. Firstly, knowledge pertaining to test-object dynamics is directly employed in its development. Secondly available information on possible modes of failure in the overall system can be conveniently incorporated into the formulation.