CaCl vs Insitu Yet Again - Printable Version
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CaCl vs Insitu Yet Again - Ernesto - 08-30-2010 12:46 PM
I always wanted to run a cacl test over 6mil but never had the time.
But ....I would like to do cacl and insitu tests on an open slab, then cover with 6mil and then perform the tests over after a week or so. Some cacl tests on top of the 6mil and then a cut out area for some more cacl tests that were all sealed up tight to the 6mil.
Perhaps this is the missing link to matching up cacl tests to rh testing. And as far as I know no one has ever done this before. The tests were compared to each other on an open slab, yes or no?
The cacl tests on top of the 6 mil would be just for giggles of course.
Anyone out there want to donate some testing kits and Rapid RH probes for my unscientific experiment?
RE: CaCl vs Insitu Yet Again - eaadams - 08-30-2010 11:21 PM
You can run cacl tests on glass and get some result. It is a crap test.
RE: CaCl vs Insitu Yet Again - Ernesto - 08-31-2010 07:05 AM
Seen all of Howards video's, thanks.
However what I am saying and I believe no one has mentioned it before cept me is that out in field tests no one has performed side by side cacl tests and rh tests where the slab is covered with a non-permeable covering having the cacl test cut in and sealed around the covering.
This might change Howards little graph a bit and give you more matching points. But heck, who wants to buy a thousand sf of plastic for every three tests. Just sayin ho ho
And according to my friend Bob, no moisture test can guarantee your NOT having a flooring failure. And I believe that because like Howard says there is so many variables, for one the water to cement ratio effects the flo of mve to the top, is 75% better than 90% rh if the 70% slab allows moisture to run to the top faster?
RE: CaCl vs Insitu Yet Again - eaadams - 08-31-2010 11:14 AM
(08-31-2010 07:05 AM)Ernesto Wrote: Seen all of Howards video's, thanks.
We've had this done on failures. But the quality of the seal of the test would be in question as by the time a floor failure has occurred the floor covering has seams coming loose and pops all over the place.
I bet a carpet tile (C&A) manufacturer has done this but carpet tile is not 100% non-permeable due to the seams.
I think a better lab test would be to test the perm rating of the floor covering via ASTM F1249 and ASTM E154. I've asked for these sort of test but have never gotten them.
RE: CaCl vs Insitu Yet Again - Ernesto - 08-31-2010 02:18 PM
Quote:We've had this done on failures. But the quality of the seal of the test would be in question as by the time a floor failure has occurred the floor covering has seams coming loose and pops all over the place.
Wondering what that non-permeable covering was. And...what were the values?
Obviously in performing tests on open slabs the value of the cacl test is going not going to be consistent and vary wildly like Howard's graph shows. But letting the moisture equilibrate with a non-permeable covering with tightly sealed seams would effect some sort of consistency in matching point values. I saw your post of ajoining (new word) test but it did not differentiate which were which, open or covered.
New slabs out here are often covered with plastic to help curing.
RE: CaCl vs Insitu Yet Again - eaadams - 08-31-2010 02:36 PM
(08-31-2010 02:18 PM)Ernesto Wrote: Wondering what that non-permeable covering was. And...what were the values?Can't say - still in litigation.
(08-31-2010 02:18 PM)Ernesto Wrote: New slabs out here are often covered with plastic to help curing.Yes, same here or they use a curing compound. (Spray and Pray). I wouldn't call curing sheets impermiable since they pull them up at the seams to wet the slab. What I am talking is 5-10 years after construction.
RE: CaCl vs Insitu Yet Again - Ernesto - 08-31-2010 04:09 PM
They also use the spray we call it Monkey blood cus it is redish, cept the better concrete guys are starting to use 6 or 8 mil, usually the commercial ones and some actually use red duct tape on the seams.[/align]. I bet it's really the architect specing it. Who knows.
RE: CaCl vs Insitu Yet Again - CC Solutions - 09-20-2010 02:40 PM
Let me throw out a couple of quick points to consider:
Moisture doesn't move laterally through concrete. It moves upward and downward, not sideways. There isn't much value in covering a slab with plastic during your test.
CaCl measures (albeit inaccurately) the amount of water vapor emitted under the dome the CaCl is housed in. The amount emitted will vary depending on the amount of moisture in the slab, the amount of vapor drive between the slab and the atmosphere, the porosity of the concrete, and the porosity of the concrete surface. A burned concrete slab can be very wet yet have a low MVER. A sealed concrete slab can be wet with a low MVER. This will show low readings on CaCl testing while the RH will be high. The POTENTIAL for failure will be there with a high RH.
I should copyright that word.... Potential for failure is the phrase I use all the time and people seem to understand it much better when I phrase it like that.
RE: CaCl vs Insitu Yet Again - eaadams - 09-20-2010 02:48 PM
Moisture DOES move sideways in incorrectly constructed slabs. If there is a sand blotter layer it will move sideways especially down joints.
Moisture does not move sideways through labcrete.
RE: CaCl vs Insitu Yet Again - CC Solutions - 09-20-2010 03:06 PM
(09-20-2010 02:48 PM)eaadams Wrote: Moisture DOES move sideways in incorrectly constructed slabs. If there is a sand blotter layer it will move sideways especially down joints.
I stand semi-corrected. Moisture can move through joints and along steel rod, and especially through a blotter layer. But for all practicality, moisture moves through concrete vertically.