The dynamic loads delivered by random vibration exciters to test items are commonly described by a power spectrum of the shaker table acceleration. For test items with resonances, the potential damage to a test item delivered by two vibration tests with different power spectra is difficult to predict. This article proposes a new method for describing the shaker table motion that relates directly to the possible damage experienced by a resonant test item, independent of its natural frequency. The new descriptor, called the damage potential spectrum, is easily computed from an acceleration power spectrum. It is applicable to all random signal driven electro-dynamic and electrohydraulic shakers, but is not rigorously applicable to pneumatic hammer-driven (repetitive shock) shakers that are commonly used for environmental stress screening vibration tests, except at frequencies above about four times the repetition rate of the hammer impacts.
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