Some Guy wrote:

Steve B wrote:

I want to pour some Sonotube bases for a metal awning and use the
weight of it to hold down the 3" x 3" x .120" posts.

You mean the posts are 10-feet long, right?

You can get 3"x3" posts that are 10-feet long?

The posts come 20' long each, and I can cut to length.

When someone says "post", I think of wood. Rectangular wood posts. Not
metal pipe.

The key here is the ".120" which is the wall thickness of the square
tubing.


I live in a very dry climate. Exposed structures made of
wood don't do as well as metal because of the freeze/thaw
cycles. Wood dries out and cracks here really bad.

Cracking I can understand, but if it's so dry I don't see how there can
be freeze-thaw cycles without some humidity or water getting into the
wood.

I'm with you there, no moisture = no freeze/thaw, just drying and
cracking and general weathering from the high desert winds and sun.


I live in the great-lakes area. We have lots of humidity and
freeze-thaw cycles in the winter. Exposed wood (like fences) don't seem
to suffer cracking or dammage from freezing and thawing (but fence posts
and fence runners do seem to warp over time - probably because of post
movement below grade).

I did the last Sonotube bases out of 30" tubes.

That's insane. I wouldn't have thought that sonotube cardboard was
strong enough, but I guess it's a function of height more than width or
diameter.

It's circular benches for posteriors or plant pots around the 3"x3"
post.


I used a total of 2 cubic yards for the three bases,

That's insane. That's about 6600 lbs. I would never want that much
concrete to hold an awning up. Expecially above grade. What an eyesore
that must look like. Lots of wasted space taken up by that concrete.

See above. Also consider the wind load of this big awning in the high
winds.