Concrete form ties washer
BeckenMung
| Posted in General Questions on
I am seeing all of these after the forms were removed by the contractors. Should the form ties washer be removed and patch before doing waterproofing and backfilling?
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Replies
Yes. Hydraulic cement is a traditional material for that application.
So hydraulic cement should be apply like a tiny bump to cover them?
If possible, remove the washer and either hit the tie with a hammer or bend it back and forth with pliers and it should break off, leaving a divot that you fill with cement.
If your foundation coating were a rubberized, elastomeric compound you wouldn't have to fill the holes separately, and I'm sure that plenty of contractors rely on asphalt emulsion damp-proofing alone. But I have seen leaks at rusted-out form ties so I prefer to make sure they are well-sealed.
The ties will eventually rust back into the concrete and start to cause spalling, which is another reason to snap them off and fill the holes. In commercial structures, a common way for structural concrete columns to fail is for the rebar to get exposed enough to rust, then the rust goes back into the concrete and starts causing chunks of concrete to split off from the column. Iron expands when it rusts, so it's similar to how freezing water inside pipes can cause the pipes to rupture.
Bill
The washer cannot be taken off easily because the is a bump on the rod the lock it in place. I wonder why my contractor used this snap tie system but not the plastic cone one. He told me that if patching is needed, it is additional scope. Now, i just patched those washer and rod ends with patches of polymerized concrete repair to cover the whole thing like a tiny hump.