It was used to secure the wall mounting bracket of the garage door opener's tee rail to the concrete wall of the house above the center of the garage door opening. The bolt was inside an expanding sleeve. The tapered head was inside the wall with the threaded side sticking out, for the bracket to go over and be secured by the nut.
Probably in place for half a century, over the years it got increasingly loose, wiggling around a lot but still difficult to remove due to the expanded sleeve. Lately, I noticed problems with the garage door opener and chain vibrating a lot and managed to pull out the loose bolt this time. Now I'd like to know:
What is this bolt called? (in case I should get a replacement)
How is it to be secured? (to prevent the garage door opener from damaging itself or the from chain popping out of place, the latter of which has happened a few times recently.)
Is a hole drilled in concrete, and the bolt and sleeve inserted, which then expands as it is tightened? Or should they be stuck in concrete when wet and allowed to cure?
The latter seems like it might not allow the expanding functionality of the sleeve to work. Since there isn't concrete residue on the bolt and sleeve, I'm guessing the former approach was used?
Also, I'm thinking there should be more than one bolt, but that's for another question...
Click images to expand.
Some close-ups, showing the main over-enlarged hole and three other unused shallow holes. Note also that due to the loose bolt, the mounting plate rocked vertically and created a wedge shaped indentation in the concrete, allowing/causing even more rocking.