Concrete drilling wedge anchors

Old 09-25-19, 05:28 PM
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Concrete drilling wedge anchors

I am installing railing on 2nd story cement deck(walk out basement). What I have are 5 slabs 82x 126 at 5 thick. The problem I have is that one post lands only 1 away from edge where 2 slabs meet. There is approx 1/8 gap between the two slabs. Will grouting between the two give it enough latteral support to not blow out edge?
Old 09-25-19, 05:51 PM
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If your anchors will be within 1" of the slab edges, I would simply not use the holes that are 1" away from the edge... too risky. If you can use the other 3 sides of the post to anchor, do that... even if it means drilling a new hole.
Old 09-25-19, 09:09 PM
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The post foot actually straddles the split. The strength in the post from being pushed outward would definitely nee to be inside and out. I kinda afraid of bolting down horizontal with railing and losing that stability but if I blow off edge it is worse. So you would also be very hesitant on a high psi grout to keep all tight as 1 solid?
Old 09-25-19, 09:15 PM
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This is one problem that could surely use a picture for clarification..... How-to-insert-pictures.
Old 09-25-19, 11:56 PM
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I just installed a bunch of 1/2" anchors in my shed slab, and I was 2" from the edge and had no issues although I had some concerns.

I dont think the grout is going to do anything, the issue is the stress within the slab regardless of what is on the outside!

What dia of holes?
Old 09-26-19, 02:22 AM
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You can you put a flat piece of 3/16 steel over the gap in the concrete and anchor the railing to that then anchor steel to concrete farther away from the gap.
Old 09-26-19, 05:58 AM
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When making your holes, use a hammer drill and not an SDS (plus or max) hammer drill to prevent major blowout or damage from drilling.
I can't see the anchor breaking the concrete 1" from the edge. These anchors tend to not be strong enough to produce the excessive force required if the concrete is in good shape.

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