I want to be able to place removeable galvanized steel 4"x4" posts
in a concrete sidewalk such that when removed, the sidewalk has
nothing protruding beyond the flat surface.
I think I've seen something like this on Moffett Field, near the big
hangar (but it has been several years).
It might be analogous to how volleyball or tetherball poles
are installed, but I am not sure how that is done and not sure
that the solution would scale up to 4"x4" posts from volleyball
sized posts.
The posts are for a wood roofed carport awning, so ideally
they would be anchored firmly to the ground so that the wind
does not invite the awning to think of itself as an airplane
and fly away :-)
TIA...
Bob Morrison - 11 Apr 2005 15:30 GMT
In a previous post z says...
> The posts are for a wood roofed carport awning, so ideally
> they would be anchored firmly to the ground so that the wind
> does not invite the awning to think of itself as an airplane
> and fly away :-)
If this is for a wood roofed structure, how are you going to lift it
high enough to get the poles out of the ground?
This doesn't sound like a very good idea to me.

Signature
Bob Morrison, PE, SE
R L Morrison Engineering Co
Structural & Civil Engineering
Poulsbo WA
z - 19 Apr 2005 21:11 GMT
The top would would be able to be disassembled in pieces, e.g., by
bolts.
Although wood is one possibility, another possibility is canvas
or equivalent.
I'm tired of the plastic stuff that disintegrates in sunlight
after a couple of years.
One benefit to a removable structure [at least, so I believe] is that
it does not require a building permit.
...
> If this is for a wood roofed structure, how are you going to lift it
> high enough to get the poles out of the ground?
>
> This doesn't sound like a very good idea to me.
Bob Morrison - 19 Apr 2005 23:13 GMT
In a previous post z says...
> One benefit to a removable structure [at least, so I believe] is that
> it does not require a building permit.
Depending on the jurisdiction this may not be true. Think mobile homes.
They are removable, but do require permits to install.
Where I live one can build up to 120 sq.ft without permit. This allows
for small sheds such as you are contemplating.

Signature
Bob Morrison, PE, SE
R L Morrison Engineering Co
Structural & Civil Engineering
Poulsbo WA
z - 20 Apr 2005 09:08 GMT
Hmm, mine would be about 10x40 as currently contemplated
(that is, enough room for two cars end to end, plus fudge factor
for tools and whatnot... hmm, maybe if I stick to canvas... ;-)
> In a previous post z says...
> > One benefit to a removable structure [at least, so I believe] is that
[quoted text clipped - 5 lines]
> Where I live one can build up to 120 sq.ft without permit. This allows
> for small sheds such as you are contemplating.
...
Joe - 22 Apr 2005 23:58 GMT
My neighbor put up a canvas single car "garage".
The town made him take it down.

Signature
JerryD(upstateNY)
Hmm, mine would be about 10x40 as currently contemplated
(that is, enough room for two cars end to end, plus fudge factor
for tools and whatnot... hmm, maybe if I stick to canvas... ;-)
z - 25 Apr 2005 01:29 GMT
Many of the hardware stores in my city sell the 10'x20' plastic
car tent. In the past I took two of these, put them end to end,
and made a 10'x34' car tent-- either no one from my city complained,
or no one noticed. ;-)
> My neighbor put up a canvas single car "garage".
> The town made him take it down.
...
Andy Asberry - 12 Apr 2005 04:46 GMT
>I want to be able to place removeable galvanized steel 4"x4" posts
>in a concrete sidewalk such that when removed, the sidewalk has
[quoted text clipped - 14 lines]
>
>TIA...
I assume you intend this to be a permanent structure that can be
removed sometime in the future.
If that is the case, I would weld 6x8 quarter inch plates on the
bottom of the posts and secure those to the concrete with 4 wedge type
bolts. Bolt size and number of posts will be determined by the size of
the roof. If the carport isn't attached to a building, you would need
some diagonal corner bracing at the top of the posts.
z - 19 Apr 2005 21:19 GMT
Thanks! This sounds as if it would work.
This solution would have the benefit that the concrete can be poured
immediately and the remainder of the design could be deferred
until later in the summer when there's more time to plan.
The notion of diagonal bracing at the tops of the posts is reminiscent
to me of late 19th century barns or horse stalls. I hadn't given
it a lot of thought myself but I had been thinking in the direction
of diagonals running from the bottom of one post to the next adjacent
post. The idea of putting them on the top, though, allows easier
passing between the posts for access. I'm guessing I would probably
use plates and bolts at the joints, maybe (?) some more welding.
Any other alternatives out there? [Frankly, though, this one sounds like
a winner to me.]
> >I want to be able to place removeable galvanized steel 4"x4" posts
> >in a concrete sidewalk such that when removed, the sidewalk has
[quoted text clipped - 23 lines]
> the roof. If the carport isn't attached to a building, you would need
> some diagonal corner bracing at the top of the posts.