Anchor depth

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Evan Dutch

Evan Dutch

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Hey guys

I’m going to be installing concrete wedge anchors for my lift. I’ve never installed concrete anchors before. The total length of the anchor is 5 1/2 inches with a diameter of 3/4 inches. If this is going into 4 inches of concrete I would drill all the way through the concrete correct? Since once you tighten the nut on the threads of the stud, it will pull the anchor to the proper depth right?

Thanks
 
mopowers said:
Have you asked the manufacturer of the lift what they recommend? Most require more than a 4" footing.
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they said 4in of concrete will work. I had two squares poured 12in deep when my pad was poured. Unfortunately the lift will have to be placed where some of the anchors will not be in the 12in deep sections
 
No way in holy hades would I trust a lift anchored in 4" of concrete. Mark where the lift towers will go, break the concrete up, dig down to 12", refill with concrete, let it set and then mount the lift.

I don't give a damn what "they" said.
 
mopowers said:
I can't see how a concrete anchor can work as designed if it extends past the concrete.
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They sure do. The anchor expands as it tightens. It doesn't matter if the anchor hole is all the way through.
 
Concrete wedge anchors have been phased out recently in our industry. (Concrete tilt up buildings). They are almost always problematic. Look up Simpson strong tie titan hd fasteners they have become the new industry standard. Once they are in they do not come out. I agree with Rusty, pour correct depth footings and instal the correct length anchors.
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It will matter of you drill all the way through the slab also, regardless of thickness. When you do that it punches out the concrete the last inch or two of the hole and looses some of its strength. If we do that the inspectors will fail the attachment.
 
Yall have misinterpreted what I said. I said it's ok to drill all the way through, not put the wedge below concrete depth. As long as the concrete is deep enough, all is well.
 
Also if you drill thru the concrete,
Any moisture coming up from the ground will get to the bottom of the anchor. Rust and corrosion follow a lot sooner than if it goes into a blind hole.

anchored lifts work but the concrete needs to be thicker. When I poured my floor for my lift, the manufacture suggested 6” 5000psi reinforced with either wire or fiberglass hairs at a minimum. Think about the foot size of the lift vs the leverage of the height of the lift with an unbalanced load- engine front heavy car. 4” will not cut it. just my 2 cents.
 
Evan Dutch said:
Hey guys

I’m going to be installing concrete wedge anchors for my lift. I’ve never installed concrete anchors before. The total length of the anchor is 5 1/2 inches with a diameter of 3/4 inches. If this is going into 4 inches of concrete I would drill all the way through the concrete correct? Since once you tighten the nut on the threads of the stud, it will pull the anchor to the proper depth right?

Thanks
Click to expand...

If it's a 2 post lift, no way I would even think about trusting 4 inches of concrete.
 
Is it a 2 or a 4 post?

4" should be good for a 4 post and sometimes anchors are even optional.

A 2 post should not be used on a 4" slab AFAIK.
 
YY1 said:
Is it a 2 or a 4 post?

4" should be good for a 4 post and sometimes anchors are even optional.

A 2 post should not be used on a 4" slab AFAIK.
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Wait?!? What? I just reread post and realized it never mentioned 2 or 4 post lift.
Sorry for my “Uncle joe rant.” As I though it was a two post. My apologies for assuming it was 2 post. Just looking out for your safety dude. Please advise 4 post or 2post. Pictures help too!
 
Evan Dutch said:
Hey guys

I’m going to be installing concrete wedge anchors for my lift. I’ve never installed concrete anchors before. The total length of the anchor is 5 1/2 inches with a diameter of 3/4 inches. If this is going into 4 inches of concrete I would drill all the way through the concrete correct? Since once you tighten the nut on the threads of the stud, it will pull the anchor to the proper depth right?

Thanks
Click to expand...

The ones i have seen are 1'' bolts/anchors , you are probly going to have a problem w/ only 4'' of concrete , on a 2 post lift!
I`d weld/tie the upper parts with cross bracing to ur ceiling, both ways !!
Epoxy the bolts too .
 
RustyRatRod said:
They sure do. The anchor expands as it tightens. It doesn't matter if the anchor hole is all the way through.
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Sure, I wouldn't worry about a hole that goes all the way through, but there's no way I'd trust an anchor that extends below the concrete. Especially 1-1/2"! That's probably close to being longer than the wedge portion of the anchor. That's what the OP is asking about.
 
It's a very simple procedure to bust up the concrete, dig deeper and pour new. Nothing to it. If you fail to do this, you have no one to blame but yourself when you get killed. Or a loved one. Your wife......your child, friend, dog......whatever.
 
mopowers said:
Sure, I wouldn't worry about a hole that goes all the way through, but there's no way I'd trust an anchor that extends below the concrete. Especially 1-1/2"! That's probably close to being longer than the wedge portion of the anchor. That's what the OP is asking about.
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Right. We agree all over that. Also, the rust and corrosion thing that was brought up was a really good point, too.
 
Alright guys. I appreciate all the input. It is a 2 post lift 10k pound capacity. The slab is average 4in thick at 4K psi with 2 squares I had poured for the posts around 12 in deep. I’ve measured incorrectly at first so the post squares won’t exactly work. I’ll take pictures in a few so you can get a better understanding of my situation
 
If I was going to break out and repour a section of the concrete floor to make it thicker, I would also make a template to match the anchor bolts and cast in L anchor bolts. I’d also side drill into the sides of the new hole and place pins into them before pouring, to tie the new concrete into the existing.
 
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