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Re: Welding Code AWS D1.1

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Karim,

I'm afraid that I did not make myself clear.  The junction of the 8" flange 
and the 14" flange creates a re-entrant corner simply from the difference in 
sizes.  (The same thing occurs when you have a difference in flange 
thicknesses.)  Therefore, the theoretical stress at the re-entrant corner, 
*regardless of the tension stress level in either the 8" flange or the 14" 
flange,* is *infinity!*  Eliminating the re-entrant corner changes the stress 
level significantly.

The AWS requirement *doesn't say* that the stress level in the 14" wide 
flange is a problem; what it says is that when you have a re-entrant corner, 
*you have a problem* and to correct it, you *have to eliminate* the 
re-entrant corner.  The problem is the re-entrant corner, not the widths or 
thicknesses of the flanges meeting, although the different flange widths or 
thicknesses create the problem.

A. Roger Turk, P.E.(Structural)
Tucson, Arizona

Karim Hosseinzadeh wrote:

. > Roger,
. > Thanks for your comment. I do agree with you with regards to stress
. > concentration around a round hole. I consider this case a lessening of
. > material due to hole cut outs, whereas in my case the stress is first
. > induced in the 8'' flange and then transferred to the 14'" flange. Now
. > where is the logic in this that the 8" x1/2 flange can safely withstand 
. > the load but the 14 5/8 x 15/16 flange may become overstressed and develop
. > cracks. Unless it is shown by tests that the smooth transition is needed 
. > to prevent  the overstressing of the smaller flange.
. > Sincerely,
. > Karim Hosseinzadeh
. >