Carport using unusual construction method

Kern Dog said:

So.....No rebar.

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Right, no rebar. I think the cement-filled pipe through the center of the pillar, plus the cement bonding/fortifying agent that I am using, make it quite strong. The fortifying/bonding agent results in a product quite different from cement in which only water is used to wet the mix.

As I said earlier, there is a lot less wobble in the supporting structure of this build, prior to adding the rafters and sheathing, than there is in a conventional frame build, signifying that the completed build will have less wobble than a frame build would have.

Okay. Keep in mind that cement and concrete are not the same thing. Cement is a component of concrete. Concrete consists of rock, sand and cement which is actually a glue or a bonding agent, used to hold it all together. The rebar acts as a skeleton to bind the concrete together to resist tension. Concrete in itself is excellent at resisting compression. This is why it is an excellent material for driveways, columns and walls. It is the imbedded reinforcing bar that gives concrete the ability to resist deflection in overpasses and bridges.
I see that you mention a concrete filled steel pole. Obviously the job has been done now and all that you can do is hope that it holds together. My thought though is that part of what makes rebar better idea is that the irregular surfaces of the rebar make a better "grip"for the concrete to grab. A smooth pole sorta reminds me of a fence post in concrete. Sometimes when one is pulled out of the ground, they slip right out of the hole, sometimes the whole chunk of concrete comes with it.
I am not trying to piss in the punch bowl here. Sometimes unusual stuff works out quite well and becomes the new way to do things.

There are no forces on the pipe that will be trying to rip it out of the concrete. Both the column and the pipe are in compression. Believe me, if you could give one of these columns a hug and try to wiggle it, you would agree that it is stronger than the equivalent frame construction.

It may be a great design that holds up just fine. Earthquakes around here are pretty rare.

I am making progress on the concrete-pillar carport.
Big thanks to FABO member "adriver" for pointing out that the roof pitch I had originally planned was too small. So I built pony walls on top of the front and middle rows of joists to raise the pitch to 2-1/2" in 12", which I believe is adequate to permit the use of asphalt shingles.
The only way I could find to cut the bird's mouths accurately in the rafters was to mark and cut them in place.
It's a lot of work to install the rafters, but I am going to take a break and install some roof sheathing for awhile where the rafters are already installed. Then I will be able to start moving my cars out of the garage. I am really looking forward to that.
Even with only about half the rafters installed and no roof sheathing, the structure sure does seem solid.

Bill Crowell said:

Thanks, adriver! You are right about the pitch. It's only about half the pitch that shingle manufacturers recommend. I really appreciate that you pointed this out. I am going to have to add a Grace Ice and Water Shield underlayment (or the equivalent) on the roof sheathing, before laying down the tarpaper.

My shop next to the carport has Hardiboard lapped siding, which is a masonry product and quite resistant to rot. I have caulked all the Hardiboard overlaps thoroughly with DAP "Custom Flexible Patch" elastomeric patching compound, which is the caulk that Hardiboard recommends. I really like the Hardiboard, even though it is a bit difficult to work with, and it has been really waterproof after painting and caulking with the elastomeric patching compound. No leaks whatsoever inside the barn from driving rain.

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I see everyone has asked the questions I was thinking as I read all this, except, did u vibrate the wet cement to settle it w/o air pockets when u poured the poles ????