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Vibration Analysis for Structural Floor Systems

Vibration Analysis for Structural Floor Systems

Vibration Analysis for Structural Floor Systems

(OP)
Is anybody familiar with "Vibration Analysis for Structural Floor Systems" Published in Journal of the Structural Division -- Proceedings of the ASCE, October 1961 ?

The above mentioned article provides the following equation to calculate the natural frequency of a simple beam, undamped, with concentrated load in the middle:

F = 187.5 / sqrt(deflection)

There is no explanation given on how this formula, or to be more specific, the coefficient '187.5' was arrived at.

If classical f = 1/2PI * sqrt(g / deflection) is used the same coefficient would be 3.13
{ = 1 / (2*3.14) * sqrt(32.2 * 12) }

The first equation results in natural frequency to be about 60 times higher.

Any thoughts?
Thanks,

RE: Vibration Analysis for Structural Floor Systems

Maybe a stupid thought but could it be units.... factor of 60 when dealing with frequency seems like it might be related to built in conversion in one and not the other?

RE: Vibration Analysis for Structural Floor Systems

(OP)
bookowski, obvious answer to a simple question :)
They did say that equations are expressed in cycles per minute.

thanks a bunch!

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