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I am attaching a plate that will carry an 80 lb bike rack, to a concrete wall, the 30" ~ 75 cm wall on the edge of the garage.

The plate has 11-mm (7/16") holes and the bolts that came with it are 9-mm (just shy of 3/8"), but those bolts are for wood studs, and so I need to choose a concrete anchor.

I see on the market three styles: Tapcon, an expansion anchor, and a sleeve anchor, which appear in the image below from left to right.

tapcon, expansion, anchor, and sleeve anchor

The first seems to be the one to use by default, but after learning that concrete walls in home garages do not have rebar, I'm nervous about the risk of splitting the concrete when inserting the Tapcon. I'd prefer to have some material, preferably a compressible one, between the bolt and the wall. Does either an expansion anchor or a sleeve anchor provide a softer jacket that will reduce the risk of splitting concrete?

Edit

Let me just add one observation for those contemplating one of these three fasteners as a potentially removable one, sometime down the road: In the expansion anchor (the middle one) one can remove the nut, but may not be able to remove the anchor. The Tapcon and the sleeve anchor appear to be entirely removable.

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  • You're talking solid concrete, and not concrete block, right?
    – Huesmann
    Commented Jun 9 at 15:09
  • @Huesmann A house's foundation is usually concrete. Then both in the basement and around the garage, that concrete is poured just a little higher (to about knee level). I would be drilling in that "rising curtain/skirt" of concrete. Is that "solid concrete"? (Also, what is a "concrete block"? Is it one of the portable blocks used to direct traffic, for example?)
    – Sam7919
    Commented Jun 9 at 15:27
  • You didn't say the wall was a foundation wall...and basement walls have been made with CMU too for decades.
    – Huesmann
    Commented Jun 10 at 12:28
  • If I were installing something into a material that I would be concerned about splitting or cracking, I would NOT want something that would expand (like the expansion & sleeve anchors). IMO, the expansion part is the one most likely to cause and issues. However, as noted in the (currently) accepted answer, that's most likely not going to be an issue for you at all.
    – FreeMan
    Commented Jun 10 at 13:04
  • @FreeMan But do I need to worry about concrete cracking when the bolt will carry a relatively light < 100lb load? Also, Tapcons exert pressure during installation. I can't sense whether they would continue to do so afterwards. The beauty of the other two is that the more load one adds, the more pressure they exert, and if they're installed to be "just snug" without overly tightening, then any subsequent expansion is indeed needed to handle the load they're carrying.
    – Sam7919
    Commented Jun 10 at 14:44

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None of these should split concrete if you predrill the right size hole for that anchor and you aren't trying to install into concrete not much larger than the anchor hole. Read and follow instructions. Be aware that drilling concrete is going to require a hammer drill in addition to the appropriate carbide-tipped bit(s).

You should predrill for wood screws too, though there it it's to avoid splitting rather than because you have to predrill to install at all.

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