The calculation of modes and frequencies of a modified structure from those of the unmodified structure

Edwin T. Kruszewski, John C. Houbolt
naca-tn-2132
Jul 1950


A method is developed for the calculation of the natural coupled or uncoupled frequencies and modes of a structure with modifications, such as the addition of concentrated masses or springs, directly from the known modes and frequencies of the unmodified structure.

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