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RE: Layout Prevents use of Drag Struts

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I don't think that you will be able to create fixity at the base of the
column with two bolts. In addition, I think that you will find that the size
of the steel is pretty large for one column with 4800# applied at the top.
The deflection will also be a problem with this much load if you try to keep
the column as light as possible. If possible, I would suggest that you try
to use a number of columns and create a grade beam connecting them (or a
rectangular footing for each one if the spacing is too far.
The trick is to embed the column through the grade beam and rest is on an
erection pad that carries only the gravity loads of the columns. The moment
will occur in the center of (or at the bottom depending on who you speak to)
of the grade beam. The grade beam is designed as a beam with an applied
moment and the gravity loads are essentially ignored and picked up on the
erection pad.
In Los Angeles, grade beams are required to be constructed with 3000-psi
concrete so as to force inspection to verify the size and placement of all
horizontal steel and ties. Regardless of whether your calc's require shear
ties, I highly recommend their placement (#3 ties). You should space two
ties at 3" apart within the first 6" of distance from the columns, then 6"
apart at the next 6" and then d/2 with a maximum of 12" on center from there
out (until you reach the next columns). Check local codes to see if they
agree or have additional requirements. For the loads you are indicating, I
would think that you could get away with a grade beam somewhere around 12"
wide by 12" deep (but of course verify this by analysis).

I don't recommend that you try to obtain fixity by bolted connection. It can
be done, but now with a lightweight connection as you indicated.

Finally, be sure you check the bearing pressure of the grade beam or
rectangular footing on the soil below to be sure that it is long enough to
distribute pressure. I am not sure, based on your area, if you need to
increase the lateral load by the equivalent of 3Rw/8 (or the latest R of 2.2
for cantilevered columns) but you need to insure that your columns are well
within allowable deflection as compared to adjacent walls in each line of
shear. This is where the idea of balance in stiffness is most important.

Good luck,

Hope this gives you some additional guidance.