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RE: 1997 NDS Equation Error?

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Mark Swigle wrote:
First a moot point: Using your numbers above, you should have gotten 2100
lbs for Ziiim, not 3156 lbs.

Not a moot point Mark. Thanks for pointing out the error. I messed up
transposing my spreadsheet to calc one bolt size to calculate all bolt sizes
at once.

Second, I have always used the version in the 1994 UBC, where the term in
question (in the formula for k1) is shown *outside* the radical.  Using the
formulas that way, my numbers always agree with the tables in the 1994 UBC.

Outside the radical is correct. I looked in my Breyer Book, design of wood
structures, and I see I had crossed out the extent of the radical for k1...
apparently, I had noticed this before.

Third, you should use Fem=Fes=5600 psi, not Fem=6000 psi, for
wood-to-concrete connections.  At least that was the way in the 1991 NDS and
the 1994 UBC.  I realize that AF&PA's Technical Report 12 shows that the NDS
tables are based on Fe=6000 psi for concrete, but I don't know if the new
NDS tables have been updated for this.  Let's stick to the old way for now
(for purposes of this message, that is).

The 97 UBC still says to use the double shear value of twice the thickness
of the side member with Fem=Fes based on wood to wood. The 97 NDS, says,
single shear, Fem=6000 psi for (2000 psi concrete - other values for other
strengths of concrete not given), tm=6" min. Yes it is different and the 97
NDS tables are correct and that is actually where the Fem and tm values are

Thanks for your time and comments, I appreciate it!

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