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Re: Lag screws in withdrawal from end grain

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Dennis, those are some good ideas.  Thanks.

The condition consists of two 10x10 roof beams of a house porch, one at each
side of the porch,  that are connected to the house only by their bearing on
cripple-studs in the wall.  I have an opportunity to secure the ends of each
10x10 to a newly plywood-sheathed shear panel on existing interior partitions
that align with the supported end of each 10x10.  The design load would be
strictly the tension of a seismic force due to the porch roof tending to move
away from the house.  My thought had been to use a 1/2"x12" hanger bolt: lag
threads on one end screwed into the 10x10, machine threads on the other end
coupled to an all-thread rod extended into the sheathed partition next to new
blocking between studs, with a plate and nut against an interior stud.

You are correct there are other means available the will not be unsightly, and
only a little more costly.  A detail I have used before is one of installing
the tension rod into a hole drilled parallel to the axis of the 10x10 that is
intercepted by a perpendicular hole drilled into the 10x10 (perhaps one and a
half inches in diameter) and a half-round steel rod of the same diameter as
and inserted into the perpendicular hole.  The tension rod may be secured by a
nut against the flat face of the half-round.  Tension in the rod would pull
the curved surface of the half-round to bear against the perpendicular hole.
The perpendicular hole may be concealed by a wood plug.  I think this is sort
of like your third suggested detail.

I'm still puzzled by the way the Code handled this; but I think you are right:
the condition should be solved in another way -- thanks for the warning based
on what you saw after the Northridge Earthquake.

I really like your idea for using the Wood Solutions Fair for a Listservice
Group Meeting.  I don't know yet whether I will attend the Fair (as good as it
sounds), but may show up for a Group Meeting even if I don't have time for a
day at the Fair.  I'll be watching for further details on when and where.

Nels Roselund
Structural Engineer