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Concrete anchors….

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  • #516567
    Moze
    Moderator
    Dallas, TX

    So, here’s the story. I’ve been in the midst of installing 75 signs in a parking garage. The signs are 6″h x 72″w x 1″d. They’re aluminum panels on an aluminum frame and weigh under 20 pounds. My method was to use Powers brand ‘Vertigo’ fasteners (see photo). The threaded portion is ¼” x 1¼”. Per Powers website, you drill a ¼” hole and drive them in with an impact and socket. The very first one I did, I drove it too much and stripped the concrete out. Lesson learned. From then on I eased them in. They seemed perfectly solid. Once they were driven in, I would hand-thread eyebolts into them and then hang the signs using wire rope (these are the signs I posted about where I made the jig to hold the signs…).

    Anyway, a couple of days into the project and I get a call saying one of the signs was hanging. Turns out the anchor pulled completely out of the hole. A couple of days later, I get the same call about a different sign. After I got a call about a third anchor coming out, I went back and removed the 48 signs I had installed, removed the anchors and drilled new holes for Hilti drop-in anchors (second photo).

    So, I’ve emailed Powers to see if they might have an idea why this happened. Hilti has a similar product (last photo) as the Powers Vertigo. Makes me wonder if I would have had the same issue, if it’s a better design, etc.

    Resident Sign Guy

    #516576
    cranbrook2
    Pro
    Belgrave, Ontario , Canada

    These are similar to the ones I have always used .

    http://www.constructionfixings.com/productdatasheets/shieldanchorbolttype.htm

    #516577
    jponto07
    Moderator
    Bloomington, IN

    I’ve never heard of the Vertigo anchors, but they are rated for concrete use, yes? If so I can’t see why they would fail if they were installed properly.

    Personally, I shy away from threaded concrete anchors (Tapcons included) that make direct contact with the concrete. I use a plastic insert with screws or go with the appropriate expansion anchors.

    Jon P.
    Timber Carpentry & Construction
    https://www.facebook.com/timbercarpentry/
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    #516579
    Moze
    Moderator
    Dallas, TX

    @cranbrook2 I’ve used those as well…..but not for overhead in a parking garage.

    The big concern in a parking garage is hitting post tension cable which can wind up fairly close to the surface you’re drilling into. The anchors I posted are 1″ to 1¼” long and help eliminate that from happening.

    Resident Sign Guy

    #516581
    Moze
    Moderator
    Dallas, TX

    I’ve never heard of the Vertigo anchors, but they are rated for concrete use, yes? If so I can’t see why they would fail if they were installed properly.

    Personally, I shy away from threaded concrete anchors (Tapcons included) that make direct contact with the concrete. I use a plastic insert with screws or go with the appropriate expansion anchors.



    @jponto07
    Yes, they’re a concrete anchor and are rated for 1390 pounds/tension.

    I don’t think plastic anchors are meant for overhead use. And as mentioned above, the expansion anchors are too long.

    I’ll never use the Vertigo anchors again. The drop-in anchors have never failed me.

    Resident Sign Guy

    #516583
    cranbrook2
    Pro
    Belgrave, Ontario , Canada

    @cranbrook2 I’ve used those as well…..but not for overhead in a parking garage.

    The big concern in a parking garage is hitting post tension cable which can wind up fairly close to the surface you’re drilling into. The anchors I posted are 1″ to 1¼” long and help eliminate that from happening.

    Is there any type of adhesive that you could add to the bolts going into the concrete ?

    #516586
    Moze
    Moderator
    Dallas, TX

    Using adhesive is an extra step, so it would just be compounding the problem. Not to mention you shouldn’t have to do that for an anchor rated for over 1000 pounds. The drop-in anchors are the best solution and what I should have used to begin with. Live and learn.

    I guess I was just curious if anyone else has used them and what kind of success (or failures) they’ve had.

    Resident Sign Guy

    #516587
    kurt@welkerhomes.com
    Moderator
    Owatonna, MN - Minnesota

    We tried to use the Vertigo anchors on a job and had issues with them stripping and holding also. We ended up using red Head drop in anchors with no problem.

    The project we were trying to use them on we were going into Precast. Due to the high PSI of precast, I do not think they held well. In my opinion they would hold better in cast in place concrete. I have had the same issues with Tapcons in precast.

    We have used anchors similar to the vertigo in wood and steel a lot. Just no luck with them in precast.

    #516591
    Moze
    Moderator
    Dallas, TX

    Thanks, Kurt. I’m not sure what the PSI difference is, but glad (I guess?) to hear others have had similar issues. I’ll never touch them again. It’s not worth the possible liability. Something like this could pretty much end my business and have me paying someone for the rest of my life.

    Resident Sign Guy

    #516603
    kurt@welkerhomes.com
    Moderator
    Owatonna, MN - Minnesota

    Precast concrete is typically in the 7 – 8000 psi range and cast in place is typically in the 4 – 5000 psi range. also, due to the curing process of the precast, it seems harder and more dense and also more brittle.

    Glad you found out there was an issue before there was an accident. Do you have liability insurance to cover things like that. also if you are selecting anchors, there could be some design liability also. Something to look into.

    #516606
    Moze
    Moderator
    Dallas, TX

    Yeah, I have liability, but the right person and the right lawyer could blow way past that coverage pretty quick.

    Resident Sign Guy

    #516607
    CrpntrFeak
    Pro
    Globe, AZ

    We use Tapcons a lot but mainly because that is what is quickly available to use.

    The GRK concrete screws I find are a ltitle better. So if I can find the GRKs, I use those.

    #516608
    TopNotch
    Pro
    elmwood park, NJ

    I always have a bad feeling with any anchor that screw into concrete for stripping fears.

    I feel better with wedge types.

    Working Pro since 1993

    Tom M

    #516609
    TopNotch
    Pro
    elmwood park, NJ

    Wasnt there a case about HILTI drop in anchors coming out from a ceiling in a tunnel somewhere? Or maybe Hilti used their anchors for an epoxy failure……something. Google

    Working Pro since 1993

    Tom M

    #516618
    Austin
    Pro
    Covington, KY

    I always have a bad feeling with any anchor that screw into concrete for stripping fears.

    I feel better with wedge types.

    I feel the same way, I use lots of tapcons for little stuff but and substantial sized things especially if over head something that is driven in instead of screwed in will work better IMO. I like using raw drives for anchoring 2x material and anything bigger than that we use a hilti threaded drive.

    #516621
    WoodsConstruction
    Pro
    Sudbury, ON

    I haven’t used either the Powers or Hilti, but I’ve used the Simpson equivalent and never have I had an issue, even over-tightening I’ve never stripped anything (threads OR concrete).

    How old is the concrete that your anchoring to?

    #516623
    Moze
    Moderator
    Dallas, TX

    @woodsconstruction

    The garages are fairly new, concrete is in excellent condition.

    Resident Sign Guy

    #516629
    WoodsConstruction
    Pro
    Sudbury, ON

    Maybe try putting a dab of epoxy in your 1/4″ pilot hole before the anchor for a little but of extra grab?

    Just looking at how similar the design is to the ones I use its strange that they would be pulling out.

    #516630
    TopNotch
    Pro
    elmwood park, NJ

    The thing is it’s all about the drill bit. The right bit not going in straight but oblong is weak.
    Then there is dust, it’s import to drill longer to leave space for it.

    Working Pro since 1993

    Tom M

    #516635
    Moze
    Moderator
    Dallas, TX

    Maybe try putting a dab of epoxy in your 1/4″ pilot hole before the anchor for a little but of extra grab?

    Just looking at how similar the design is to the ones I use its strange that they would be pulling out.

    I had talked to the Hilti people about using some of their epoxy along with the screw-in anchors, but it’s one additional step and it’s more money. Shouldn’t have to do that and it would just leave me wondering if it solved the problem.

    The thing is it’s all about the drill bit. The right bit not going in straight but oblong is weak.
    Then there is dust, it’s import to drill longer to leave space for it.

    I was using a brand new Bosch Bulldog Extreme bit, I definitely don’t think thats the problem.

    I set the depth setter on my SDS so I would drill a little past the length of the anchor. That being said, these were all overhead, so dust wasn’t really a factor anyway.

    Resident Sign Guy

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