Dong, Per our phone conversatoin, here is the language regarding vibrations from Guide Specifications Design of Pedestrian Bridges by the American Association of State Highway Transportation Officials, Section 1.3.2 Vibrations The fundamental frequency of the pedestrian bridge without live load should be greater than 3.0 hertz (Hz) to avoid the first harmonic. If the fundamental frequency cannot satisfy this limitation, or if the second har- monic is a concern, a dynamic performance evaluation should be made. In lieu of such evaluation the bridge may be proportioned so that the fun- damental frequency shall be greater than f > 2.86 ln (180/W) where In is the natural log and W is the weight (kips) of the supported structure, including dead load and an allowance for actual pedestrian live load. Alternatively, the minimum supported structure weight (W) shall be greater than W > 180 e^(-0.35f) where f is the fundamental frequency (Hz).
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Dong, Per our phone conversatoin, here is the language regarding vibrations from Guide Specifications Design of Pedestrian Bridges by the American Association of State Highway Transportation Officials,
Section 1.3.2 Vibrations
The fundamental frequency of the pedestrian bridge without live load
should be greater than 3.0 hertz (Hz) to avoid the first harmonic. If the
fundamental frequency cannot satisfy this limitation, or if the second har-
monic is a concern, a dynamic performance evaluation should be made.
In lieu of such evaluation the bridge may be proportioned so that the fun-
damental frequency shall be greater than
f > 2.86 ln (180/W)
where In is the natural log and W is the weight (kips) of the supported
structure, including dead load and an allowance for actual pedestrian live
load. Alternatively, the minimum supported structure weight (W) shall be
greater than
W > 180 e^(-0.35f)
where f is the fundamental frequency (Hz).
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