Concrete anchors
Concrete anchors
Anybody have a favourite concrete anchor for attaching something big to garage floor?
Looking at helping a friend install a tire changer and a "utility post" to the garage floor.
The garage is at the top of a short but steep hill, in a VERY snowy location. the post will be used to help pull stuck cars get up the hill, and broken cars into the garage for repair.
We have a commercial hammer drill to make the holes.
Looking at helping a friend install a tire changer and a "utility post" to the garage floor.
The garage is at the top of a short but steep hill, in a VERY snowy location. the post will be used to help pull stuck cars get up the hill, and broken cars into the garage for repair.
We have a commercial hammer drill to make the holes.
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You want to use wedge or drive pin anchors if a stud sticking up is ok, or drop in anchors if you need to bolt something down. Drop ins do require you to set them with a special tool or a punch, wedge just drive them in to the required depth then bolt down what you want. With stud types, especially wedge, make sure you drill the hole deep enough, drilling all the way thru isn't even a bad idea, that way you can drive a wedge anchor all the way thru to the ground if it's damaged or you don't need it any more. Do not use sleve anchors or double anchors, they have good paper ratings, but don't hold for crap. Wedge are my favorites, quick and strong.
Wedge
drop in
Drive pin.
Wedge
drop in
Drive pin.
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- Beamter
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One small point to consider- it is a pain in the butt to get the dust from drilling the hole out of the hole. This can block the hole making it impossible to get the anchor in even when the hole is drilled to the correct depth. A vacuum with a straw might work, or an air nozzle with a long tip (though that can make a mess.)
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I would think the manufacturer would have specific instructions for the anchor points, given the engineering involved and the liability. This is in no way disregarding the previous post. I must say that I have no professional knowledge in this, I neither condone nor condemn any of the above mentioned.
Last edited by David B on Nov 24, 2010 11:48 AM, edited 1 time in total.
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I would use an epoxy anchor system. Powers sells those as well. Mechanical anchors put a lot of lateral pressure into the walls of the drill hole because they expand. Because of this, greater anchor spacing is required with mechanical anchors. I would imagine your "utility post" isn't very wide. That may put your holes too close together for mechanical anchors. Epoxy anchors are stronger, but they require a clean hole and more preparation.
Patrick, you need to find how how thick your slab is and what the ultimate strength of the mix design is. If you don't know, I would rent a concrete saw and a hammer drill. Cut out a square several inches (I would consult and engineer on how many inches) wider than the foot of your post, dowel into the existing slab, and pour at least 8 inches of 4,000 psi or better concrete (with reinforcement). While you're doing this, you can imbed anchors into the concrete. Mike will probably come back and say that's over doing it and no one needs to go to that much trouble for a two post lift. That's the way I'd do mine and I would have very good peace of mind that my lift won't fall over.
If your slab is 5" thick, 4000 psi, and reinforced, you can probably just install anchors in the existing slab and be fine. Also, some lifts come with optional wider mounting plates that reduce the need for 4,000 psi to 3000 psi or so.
Patrick, you need to find how how thick your slab is and what the ultimate strength of the mix design is. If you don't know, I would rent a concrete saw and a hammer drill. Cut out a square several inches (I would consult and engineer on how many inches) wider than the foot of your post, dowel into the existing slab, and pour at least 8 inches of 4,000 psi or better concrete (with reinforcement). While you're doing this, you can imbed anchors into the concrete. Mike will probably come back and say that's over doing it and no one needs to go to that much trouble for a two post lift. That's the way I'd do mine and I would have very good peace of mind that my lift won't fall over.
If your slab is 5" thick, 4000 psi, and reinforced, you can probably just install anchors in the existing slab and be fine. Also, some lifts come with optional wider mounting plates that reduce the need for 4,000 psi to 3000 psi or so.
Last edited by tsmall07 on Nov 24, 2010 4:04 PM, edited 2 times in total.
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I like Hilti better, too. I used to be really good friends with a Hilti rep. That was awesome. Lots of free stuff.Rich Euro M5 wrote:What Tyler said... Made by Hiltitsmall07 wrote:I would use an epoxy anchor system.
Rich
My other favorite company is Sika, but I don't remember if they make epoxies or if they just do sealants and concrete patch.
If wedge anchors are correctly installed there will be a little sticking up, more than with drop ins, but not much. If someone has to cut them off they didn't drill deep enough. It happens a lot, but there's a lot of hacks out there.a wrote:When installing equipment racks to ATT seismic specs 1/2" drop ins were acceptable. a drift is all you need to set them and the bolts remove easily . Flush cutting studs is a PITA.
if I where you I would drill and use concrete epoxy to install anchors. If I was using concrete epoxy I would cut the head off of some large bolts. I am not a fan of any of the pins or wedges mentioned above. Be careful with the epoxy, it is one of the nastiest chemicals I have to use at work.
if you want to over do it the cutting, doweling, and repouring with anchor bolts is the best way. I would only recommend this if you have shitty concrete that you want to replace any way. And if you do repour it, you should add some driveway or side walk to your house so you can order a truck full. And if you use quikcrete add some fibermesh to it.
if you want to over do it the cutting, doweling, and repouring with anchor bolts is the best way. I would only recommend this if you have shitty concrete that you want to replace any way. And if you do repour it, you should add some driveway or side walk to your house so you can order a truck full. And if you use quikcrete add some fibermesh to it.
Properly installed in good concrete, wedge anchors pullout approaches tensile and shear strengths. Put them in asphalt or cinderblock and they don't hold well. I've generally found them to be non removable, ie they break before they come out. None of which is to say anything bad about epoxy, just that it's generally not needed and a bit of a pain.