Effectiveness of curing agent vs. wet cure by covering with poly sheet

[ajk1]

Does anyone know of any research paper(s) that compare the effectiveness (usually measured by chloride diffucion rate) of curing concrete by spraying on a curing agent vs. a 3 day wet cure by covering the concrete with polyethylene sheet for 3 days? I suppose it may depend on the particular curing agent (solids content, etc.) and coverage rate, but any information would be helpful. There is a paper by Hooton, Gelker and Bentz (ACI Materials Journal, March-April 2002) on this topic for mortars, but not for concrete. In speaking to one of the paper's authors, he says that this may not be valid for concrete. By effectiveness I mean the resistance to chloride penetration that would cause corrosion of rebar about 40 mm below the top surface of the concrete. The type if concrete I have in mind is that used for parking structures, viz. w/cm = 0.40, no silica fume. I am aware that concrete with silica fume required a wet cure, and a curing agent would not be as good in that case.

 

[dik]

I don't like using poly for curing... it can lead to permanent discolouration of the concrete surface. A sprayed curing agent or wet burlap is the way to go.

Dik

 

[BridgeSmith]

Not familiar with any research on the subject, but I can tell you a couple of things that may help you:

1) Contractors much prefer using curing compound for simplicity.

2) From what I've seen, precast and prestressed sections are always wet-cured.

If you're concerned about permeability to salt-laden water, consider applying a sealer, coating (methyl methacrylate, etc.), or epoxy overlay. That's what we do for bridge decks exposed to deicing salts. Also consider using galvanized, epoxy coated, or MMFX reinforcing.

 

[hokie66]

There are lots of research papers on this subject, but my google search found that you have to pay for most of the papers.

Constructability and contractor preference aside, no curing compound gives the same effectiveness as plastic sheeting or water curing. The more effective ones like chlorinated rubber and wax emulsion have environmental issues and finish compatibility problems. The acrylic compounds just don't work.