Here's the link to the online Rohn catalog.
On the left, click on the On-Line Catalog.
Then click on the GT series, then click on 45G, then click on the guy details
for the height and windspeed you're designing for. All the plans and details
you want are found on the other links.
Also here's an excellent compedium of how-tos for towers. Required reading for
any installation in addition to towers.
Also included on the above link is the K7NV assessment of different types of
tower bases and a structural analysis of each type (section in concrete, pier
pin flat base, pier pin tapered base).
Finally, I'd wait 28 days before I started loading up any newly poured concrete.
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