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Effective Vibration Length from Effective Buckling Length

Ngoji Tonye Johnarry(1*)

(1) Rivers State University of Science & Technology, Faculty of Engineering, Department of Civil Engineering, Nigeria
(*) Corresponding author



The buckling strength of columns is readily brought home to designers through the Euler length factors, \elf\, but vibration analysis still remains less design-oriented. This study develops an effective-vibrating-length, \evl\ from \elf\ and more easily computes the frequencies of any frame assemblage; in essence the \evl\ is a pin-ended bar in uniform mass replacing the given frame. The use of the \evl\ by-passes assumed shape-functions in the Rayleigh quotient method. The introduction of length allows spectral responses to be found easily. The \evl\ by-passes in-determinate structural analysis to find sway and deflection accurately in an elementary way. The effective-vibrating-length does for vibration what the Euler-length-factor does for buckling.
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Euler Effective Buckling Length; Effective Vibrating Length; Stiffness Matrix; Over-Turning Moment

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