Pete writes:
>If I put nuts every few inches on a piece of threaded stock with
>large flat washers between each pair, would this be as effective
>for holding in concrete as bending the stock into a "J"?
Good question. I recently compared the foundation plans for the "old" TX-472
to those for the "new" TX-472 (US Tower, medium-duty, 72' freestanding
crankup). Both towers are very similar. In the old plans (which reference
the 1991 UBC) they show 1" x 36" anchor bolts bent in the familiar L shape
(36" on the vertical leg). In the new plans (which reference the more
stringent 1994 UBC) they show 1-1/8" x 27" anchor rods (note change in
terminology). The rods are not bent. Here is what the specs say about them:
1-1/8' dia. x 27" ASTM A36 Anchor rods w/ heavy hex nuts. Weld nut on bottom
w/ 1/8" fillet all around. Provide dbl. nuts at base plate. (One on top &
one on bottom of plate.)
I guess the concern is that when you start torquing on those base nuts with
your 3' crescent wrench they don't want the bolts (rods) to start turning in
the concrete. Also, note the ASTM spec on the rod. This ain't hardware
store all-thread.
73 - JC,k0hps@amsat.org
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