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lag screws in withdrawal from end-grain

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Wow! take a couple of days off and missed all the fun with this one. I tried to
follow the thread through the digests and think most all the questions were
addressed. just a couple of clarifications though. the end-grain factor C_eg for
withdrawal is 0.75 and for lateral loads is 0.67. Bruce Pooley's explanation on
the background for it was correct. Roger Turk's reference to the FPL Tech.
Bulletin #597 was also correct. 

the NDS Commentary states that this situation should be avoided due to
possibility of splitting due to lateral loads. the reason the "should not"
statement was taken out of the NDS is that the code bodies are requiring
standards developers to use "mandatory" language in writing the standards. for
them, it's an enforceability issue. commentary language like may and should is
being replaced with terms like "shall be permitted" or moved out of the standard
to the commentary. probably 100 of the 130 changes to the '97 NDS dealt with
this very issue.


From: "Bill Cain, S.E." <bcain(--nospam--at)>
To: "'seaint(--nospam--at)'" <seaint(--nospam--at)>
Subject: RE: Lag screws in withdrawal from end grain

The "should not" statement does appear in the 1991 NDS Commentary.
Bill Cain, S.E.
Oakland, CA

-----Original Message-----
From:        NRoselund(--nospam--at) [SMTP:NRoselund(--nospam--at)]
Sent:        Monday, September 07, 1998 9:18 AM
To:        seaint(--nospam--at)
Subject:        Lag screws in withdrawal from end grain

The 1994 Edition of the UBC says "lag screws should not be loaded in
withdrawal from end grain.  When this condition cannot be avoided, the
tabulated nominal withdrawal value, W shall be multiplied by the end grain
factor, Ceg=0.75."

The 1991 edition has a similar statement.  I don't find the 'should not'
statement in the 1991 NDS.