We've got a number of long timbers and were thinking of making a pole barn/shop with them. NO, We're Not thinking of timber framing.
I don't want to set the timbers into the ground or the concrete slab since they will eventually rot. I want to anchor them to the concrete slab, put on the roof and then fill in the walls with standard framing. I'm not sure what kind of anchors to use on the posts. Lowes doesn't carry anything that significant.
Google "Simpson Post Bases" for what they offer, and go from there. They offer one model with a metal "plate" that raises the post off the concrete, use this type for untreated posts. I am just in the process of building a large deck, and am going to make my own bases and beam saddles. Since I am using treated lumber, I have to get them hot dipped galvanized, but that's cheap. If you don't want to square up your posts maybe some custom work is needed. If your posts are exposed, you really should use treated, which requires Hot dipped, or stainless hardware. (Decks.com is even saying stainless only)
Hammerdrill 1" holes in your slab and uses 1" rebar studs. Epoxy(two-part) them into the slab. Drill 1" hole in your timber bottoms put puddle of tar around anchor stub on concrete then put epoxy in timber hole. Set timber down onto stud. Make sure tar comes out all the way around timber. Or make brackets out of 3" x 4" angle iron. Attach to slab(3" side with 1/2" anchor) with anchor bolts and to timber with lags([email protected] 3" x 1/2").
I doubt epoxied rebar has any long term resistance to lift forces, which depending on how enclosed the building is, could be significant. Cast in place brackets with 2 bolts like the Simpson CB series or similar would be good.
Scorpster; epoxied rebar with an approved bedding epoxy is an accepted method of installing rebar in concrete although in this case it not something I would consider. The construction epoxy we use for rebar has a tensile and compressive strength much stronger than the concrete itself and meets our hurricane code requirements with the OK of an engineer or architect, and they always allow it.
Wayacoyote; depending on the size of your timber, Simpson may have an anchor for attaching to concrete with Redhead or similar anchor bolts; normally you'd use 1/2"x4" bolts minimum for this application. If no Simpson available check having a welding shop fab some simple U-type brackets and bolt those down to the slab.
Drill 1" hole in your timber bottoms put puddle of tar around anchor stub on concrete then put epoxy in timber hole. Set timber down onto stud.
This is where I see the failure happening, wood moving like it does. Especially if it's an open sided pole barn, the lift forces would be staggering. 3 years ago while driving home, I watched the wind pick up the front half of a large shop roof (30 x 80 x 16), and SLAM it into the owners house. It pretty much exploded. Same shop was built the year before, with 2 x 4 stick construction, before they could start sheathing it, it blew down. Who knew a skinny little skeleton could catch that much wind. There's a lesson in there somewhere. For my deck (1000 sq ft), I'm making my own cast in place, 2 bolt, hot dipped galv, 1/4" steel bases and beam connections (6x6 PT posts, and built up 6x10 PT beams). Simpson price....4-5k. My cost with powder coat under 1k.
if you have not poured the slab yet your choices are endless. i would decide what your finished grade is going to be, and pour 10 or 12 inch round x what ever depth gets you below frost line sonatubes with the brackets in the pour, and when that was all set up i would pour the slab with the sonatubes in it. it.s more mud, but it solves the problem of lift, keeps your posts off the concrete, eliminates frost heave on the framing (could still get the slab between posts) this may not be an issue where you are, it is here. with everything i build i try to make sure i build big overhangs to keep weather away from the framing. good luck.