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Re: Engineers involved with UBC

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Charles,

I understand this thinking for do the components and cladding
design...i.e. either windward or leeward will always govern over a
"sidewall" pressure, but there are some scenarios that might create
problems with this method when doing the main force resisting system.  For
example, say you have a large industrial plant (i.e. an automobile plant
building) that is rather long and has several expansion joints along the
length of the building.  The end portions of the building could have a
wind scenario where there is windward pressure on the one wall, leeward on
the other side of the building, sidewall pressure on one side, and nothing
(interal) at the expansion joint.  In the case of an industrial building
where the trusses are being used a moment frames, this could produce
bi-axial bending on the columns.  The UBC code does not appear to address
this type of situation adequately.

Maybe this might help explain why the question was asked.

Scott

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Scott E. Maxwell, SE, PE
Structural Engineer

BEI Associates Inc.
601 West Fort Street
Detroit, MI  48226

Telephone: (313) 963-2300                              
Fax:       (313) 962-4269

Email for Business: 
Email for Personal: smaxwell(--nospam--at)engin.umich.edu
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On Tue, 21 Mar 2000, Charles Greenlaw wrote:

> Mark Anderson posted this reply (below) yesterday. I was involved with the
> wind code formulation for the 1982 UBC also, and I agree with him. The UBC
> makes every wall a windward and leeward wall in turn, and it was deemed that
> analyzing as a side wall was non-controlling of design, and thus unnecessary
> to do.
> 
> Why AISC 7 is different I do not know. Maybe AISC does not rely on seismic
> code complexity as its basis for reputation and self-esteem, and makes up
> for it with wind code complexity. A cynic might know, if you can find one.  
> 
> Charles Greenlaw SE  Sacramento CA
> 
> >I was involved in some of the proposals concerning the rewrite of this
> >section for the 1982 UBC, and recall that we proposed the use of
> >"non-windward" walls for "leeward" walls, but it didn't fly.  My
> >understanding was that the prevailing point of view was that the issue was
> >meant to be addressed by considering as many different wind directions as
> >necessary to envelope all possible effects.  Wind loading of sidewalls
> >was/is considered to be provided for by application of leeward wall effects.
> >
> >Mark D. Anderson
> > 
> 
> 
>