STUDY ON DIRECT IDENTIFICATION OF DISPLACEMENT MODE AND STRAIN MODE BY IMPULSE EXCITATION

The theory and method of direct identification of displacement and strain modes for vibration modal test with strain guages are described. The concept of strain mobility, strain displacement relationships and derivation of formulae of transfer functions in terms of strains are considered. The system modalparameters, including the strain mode and stress mode etc., can be identified by the present method. This is a new development for modal tests of impules excitation.