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Re: Bent Bolts or Threaded Round Stock

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David,

I can't answer your question, but I offer the opinion that bending threaded
rod is a bad idea that will produce a product that is "primed for failure".

The elongation and yielding that results from the bending process will only
occur at the base of the threads because that is where the rod cross-section
has minimum diameter.  Thus, the yielding is not uniformly distributed along
the length of the rod, but is concentrated in zones of length equal to about
1/4 of the pitch for each pitch increment, making the strain at least 4
times what it would be in a plain rod.  See the sketch on page 4-147 of the
AISC ASD manual.  Try it by hand with a piece of 1/4" or #10 all-thread bent
around a small pipe or a 1" diameter bolt -- the piece becomes easy to
break.

Nels Roselund
Structural Engineer