Question for you "Contractors"

[HarryD]

Originally Posted by 911Rob

Use a Hilti Hit Epoxy anchor.

Step by step instructions: LINK

Contact the local "HILTI" supplier in your area, their salesman will explain it fully to you; these are engineered fastening systems and I can guarantee you they are the best for this application. Most every equipment/tool rental outlet will carry Hilti products.

I would not use a butterfly anchor, they can work loose and cause problems down the road (spalling).

Coring is more expensive and overkill for that application.
Make sure you "borrow" or rent the epoxy applicator gun for economics; the system is expensive, but compared to coring not.

Good luck, those are expensive benches too.

+1 on the Hilti's. This is what is often used to fasten structural pieces to concrete. For your application a propely sized set will last longer than the bench.

[Stanley]

Originally Posted by milt

Hey, you're the one leasing to the county. If it were mine, I wouldn't even give them a bench because of the liability. If I did, they would submit the plans for approval and give them to me. I would then get a contractor that has the proper insurance to do work in a public environment. I would also use a consulting engineer.

I too work in the construction industry and this is excellent advice. If they want a bench, make them pay for it. Having worked on many 100+ million dollar construction projects in the past year, covering your own a$$ is one the most important aspects of the job.

[avi8torny]

+3 on the HILTI. To bad you're not closer, I would have let you borrow mine. Any commercial rental should carry these and the fasteners.

[Danimal16]

Originally Posted by milt

I'm not an engineer, nor do I play with one , but 3 200lb. people moving about on a 2 post bench in soft soil would bring that thing down in a day or less. Captured in concrete, the base would have a much better chance, which is your condition.

Hey, you're the one leasing to the county. If it were mine, I wouldn't even give them a bench because of the liability. If I did, they would submit the plans for approval and give them to me. I would then get a contractor that has the proper insurance to do work in a public environment. I would also use a consulting engineer.

Call me careful, or whatever. I don't hardly do anything but some handy work anymore. I gave up my license and insurance. It's really too scary and too expensive to continue on. And my competition all stands at the Home Depot for any kind of job, so why would I stoop? I have assets, they have nothing.


Well, for structural, you would need a deputy inspector for foundation bolts, etc. The bench is something else, but you might need a signed engineer's report on the fasteners to be used.

Milt,

This post brings up alot of good points. The angled and multiple anchors in a large concrete base will work well. The mass of the concrete that you propose is rather inexpensive when compared to having to replace this thing. You have pretty much covered the pull out due to the bending of the bench. Plenty of ways to skin a cat here and your way would get er done.

The other points regarding the epoxy anchors add cost and frustration.

[Zeke]

I was one of the best you could find. I learned everything from the old timers that are now all dead. now, I'm the old timer. No one wants to learn from me. That's fine, as my better days are behind me. I actually can't equal my past quality anymore. But, I can remember how to do something right. Many times that's the old fashioned way.

You can't beat having your entire system holding the bench. Who knows what the depth and strength of the existing slab is? If benches were planned for that area, I would suggest that the plans would have called for some type of additional concrete or footing at their bases.

Also, be aware that the benches may need to be removed some day for whatever reason. Most of the methods suggested here would allow for that with little trouble. One of mine for slip-over posts would be more work.

A final idea is to purchase massive cast concrete benches, place them and forget them. Or, you could tack them down with some epoxy so they will never move sideways. No contractor needed.

[911Rob]

Originally Posted by milt

A final idea is to purchase massive cast concrete benches, place them and forget them. Or, you could tack them down with some epoxy so they will never move sideways. No contractor needed.

Best idea yet. That's what we typically do in this application; picnic table too. Check the precast supplier in your area.

Epoxy hits are definately "new school" and we often have challenges getting them approved by the old school croud; you can test the depth of the existing concrete by drilling a hole, as there is an assumption that the depth is adequate.

I tried to use this system for anchoring my sill plates down in a remote local area I'm building in; had to deal with an old timer building inspector. He said no way and my framer said he'd be happy to just drop the anchor bolts into the wall pour and then bolt them down after; cheaper and what the heck; so I said, "OK". But on commercial jobs where we have professional engineers and architects to deal with, it's a NO BRAINER! Way easier, turns out cheaper and faster!

Install is very simple with the right tools though.
Drill a hole with a concrete hammer drill. Fill it with epoxy. Drop in your proper bolt with washer and nut on it. Let set. Tighten nut. The concrete will break before the bolt set into the epoxy ever will. Simple. There is a special applicator gun for applying the two part epoxy.

Cheers and good luck

[911Rob]

As per Milt's suggestion; look into the concrete bench products.

Lot of good ideas here: LINK

This is the way we've been doing it for years now; great idea!