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Re: UBC: OMF connections

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At 12:25 PM 10/30/97 -0800, you wrote:
><Reference 1994 UBC section 2211.6.2, (or equivalent 1997 UBC section
>Say you're designing the connections for an "Ordinary-Moment-Frame" in a one
>or two story metal building (like a pre-engineered building) and the *wind*
>loads control over the seismic loads.  Would you still design the connection
>to be "capable of resisting a combination of gravity loads and 3 (Rw/8)
>times the design **seismic** loads" in accordance with '94 UBC sect. 2211.6.2 ?
>   Thanks.
>                Steve Gregg, PE
>                Walla Walla, WA

If I understand your situation correctly, primary system wind loads control over
primary system seismic loads.  But if 3Rw/8*seismic loads produce greater forces
at the joint than the primary system wind loads do, I believe the joint must be
designed for the increased seismic load to comply with 2211.6.2.  If the
wind load
is greater than 3Rw/8 seismic at the joint, design the joint for the wind load
instead.  Personally, I don't like to use 2211.6.2 and prefer to meet
and design the connection for the strength of the girder in flexure, even
for OMFs
is zones 3 and 4.

Joe McCormick