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FW: Cold-Formed Joist Lap Splice Question

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I have to add a little more to this discussion.  I do not think that the
way that AISI is doing this is the correct analysis.  In order to be a
continuous beam, the moment must be transferred from the single member
to the double member and act in the same manner.  Does this happen.  The
way AISI looks at it is as if the beam were a simple member with a
cantilever end.  Consider the deflection for a moment with unequal laps.
The cantilever end wants to deflect upward due to the load on the rest
of the member.  In this case it is forced down by the other member which
it laps onto.  The cantilever end wants to deflect differently than the
member that it laps onto.  In order for the cantilever to deflect in the
same manner as the beam it laps onto, the moment must be added into the
splice.  I think the technically correct way to do this analysis is to
add the vertical shear with the shear in each bolt due to the
moment(which will vary)and any axial shear that may be involved.  This
gets into a complicated analysis if you are lapping Z-members because
the neutral axis shifts where your lap is, especially if you have
different gauge members.  I used to work for a pre-engineered metal
building manufacturer.  They considered the beam to be continuous as
AISI does, but I confirmed it with the Research and Development
department that it was not the technically correct way to analyze the
connection.  It is one of those things that has worked for years so it
is considered to be OK.