Effects Of Damping Constants And Stress Distribution On The Resonance Response Of Members
Report Number: WADC TR 52-320
Author(s): Lazan, B. J.
Corporate Author(s): University Of Minnesota
Laboratory: Materials Laboratory
Date of Publication: 1953-12
Pages: 13
Contract: AF 33(038)-18903
DoD Project: None Given
PB Number: PB116818
Identifier: AD0003566
AD Number: 3566
Abstract:
The amplitude of vibration of a member at resonance, as defined by its resonance amplification factor, is analyzed in relationship to the damping properties of materials. Data are presented on damping energy to indicate the effect of stress magnitude, stress history and temperature. Based on the mathematical relationship found to exist between damping and stress magnitude the resonance amplification factors ars determined for a variety of direct stress members and beams. It is shown that the amplification in vibration caused by resonance may be considered to be the product of three basic factors: (a) the mathematical factor, (b) the cross-sectional shape factor, and (c) the longitudinal stress distribution factor. The first of these factors may be calculated from the damping and dynamic modulus properties of the material and the last two from the shape and loading characteristics of the member. Diagrams are presented to show these basic factors as functions of the damping exponent and other variables for members commonly encountered in engineering practice. Experimental data are presented to confirm the equations derived for resonance amplification factors of members having various shapes and stress distribution.
Provenance: IIT
Author(s): Lazan, B. J.
Corporate Author(s): University Of Minnesota
Laboratory: Materials Laboratory
Date of Publication: 1953-12
Pages: 13
Contract: AF 33(038)-18903
DoD Project: None Given
PB Number: PB116818
Identifier: AD0003566
AD Number: 3566
Abstract:
The amplitude of vibration of a member at resonance, as defined by its resonance amplification factor, is analyzed in relationship to the damping properties of materials. Data are presented on damping energy to indicate the effect of stress magnitude, stress history and temperature. Based on the mathematical relationship found to exist between damping and stress magnitude the resonance amplification factors ars determined for a variety of direct stress members and beams. It is shown that the amplification in vibration caused by resonance may be considered to be the product of three basic factors: (a) the mathematical factor, (b) the cross-sectional shape factor, and (c) the longitudinal stress distribution factor. The first of these factors may be calculated from the damping and dynamic modulus properties of the material and the last two from the shape and loading characteristics of the member. Diagrams are presented to show these basic factors as functions of the damping exponent and other variables for members commonly encountered in engineering practice. Experimental data are presented to confirm the equations derived for resonance amplification factors of members having various shapes and stress distribution.
Provenance: IIT