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I am starting a commerical project this week. It's been a long time since I
have done anything but custom residential, cold-form and retrofit work. This
appears to be very easy, but I have a few questions on engineering standards
which some of you might be able to help with:
The project is a Starbucks Coffee and five other storefronts. Wood frame,
TJS roof trusses (parallel chord) with sloping wall plate, tee-bar ceiling,
three solid sides and one openfront, slab on grade. A few unique features
such as a small parapet type tower structure (facade), and a covered portola
(walkway).The building is essentially 57' x 120 feet long. The trusses
(TJS)clear span the 57 feet. there diaphragm is 5/8" struct I plywood, all
side walls are fully sheathed from plate to plate. Overall plate height
rises from 12 feet to about 16 feet (3/8" per foot roof slope). Here are a
few questions:

1.  Would you recommend welded wire fabric in the slab or a more durable #3
rebar arrangment. What is the conventional layout of #3 rebar (6" o/c, 12"
o/c or 18" o/c).
2. The stores are approximately 15 feet wide, however the owner does not
want any interior partitions for load bearing. He wants to be able to
combine stores if wanted. What is the maximum slab area for installation of
expansion joints? What is the conventional slab thickness (4" or 6")
3. I intend to use embedded steel in the open front - pendulum type
columns - which conforms with the clients past conventions. Rather than
embedding into post foundations, I plan to use the foundation as a grade
beam with erection pads below (which will be bearing pads as well). I want
to develop lateral moment in the grade beam. This posses two questions:
a) should I place the grade beam below and independent of the slab edge? I
think it is a good idea since the grade beam will be f'c=3000 psi concrete
with special inspection required and also it will keep the structural
gradebeam independent of the non-structural slab. Any other thoughts?
b) Should I follow '94 code and distribute lateral according to an Rw of 6
or follow the '97 code and take the penalty for the pendulum condition?
Also, if I follow '97 UBC convention should I use the lateral component for
the entire building or just the embedded poles?

4. 3(b) leads to this question - Has the SEAOSC code committee taken a
position yet regarding embedded column lateral design. It was suggested in
their minutes that they intended to take the position that only the columns
be loaded with higher shear in order to compensate for story drift. Any
comments yet?

5. I have recomended the use of TS (Timber Strand) studs. This is a low
budget project, but I am under the impression that the labor savings in
taller walls with dimensionally true and straight lumber will compensate for
the labor cost and scrap necessary to deal with crowned, warped and twisted

Any comments you might have would be greatly appreciated. At the least,
please let me know if you think I am on the right track.

Thanks in advance for all advice.
Dennis S. Wish PE