ASTM C666 - Resistance of Concrete to Freeze/THaw

[JMackNH]

I am involved with a project that is requiring freeze/thaw testing of the proposed concrete mix design (ASTM C666). This test standard requires an extensive amount of time (14 days just to cure beforehand!). Are there any other tests that could be suggested to run in place of C666 or some other means to demonstrate freeze/thaw resistance?

 

[darthsoilsguy2]

What's your role in the job? Are you the concrete testing lab that works for the Owner to make field cylinders? Or do you work for a Ready-Mix Concrete supplier who wants to provide the mix? This test is usually done by the concrete supplier to qualify the mix beforehand and can be a good while before the project.

it has been a while since i've seen this have to be done (by others to resolve a low-air discrepancy), but i believe the 14-day cure cycle is just the tip of the iceberg compared to how long it takes to get through the freeze/thaw cycles.

You should explain the type of project you are working with as well. If you say you are working on a cast parking garage or bridge, people will say the test needs to be done because it is important and worth having... if you are working on a foundation wall, people will suggest that you approach the designer and talk about focusing on the air content testing.

if you are a testing lab and you absolutely need to do this... sub it out... there are high quality specialty labs out there that do this test who receive samples from slump&dump testing outfits.

 

[JMackNH]

Thanks for the response, Darth!

Right now the job is in the development stage. The contractor has reached out to my testing firm for advice to see if there is an alternate test method to C666 to suggest to the owner on account of possible reluctance on the part of the concrete and precast supplier. From what I gather, the job does revolve around some sort of bridge or tunnel, and not a typical foundation wall of foundation, so it sounds like they may just have to bite the bullet. I was just curious if there was a single test or a combination of methods that could be suggested to use in place of C666.

 

[TehMightyEngineer]

Hah! Funny to run into this. I work for the precaster involved. Our project manager just called me to see if I had any advice and I told him "funny, just saw a post on eng-tips about that". I also have limited experience with this test so no hard feelings that you're reaching out on here for any advice; I'd have done the same.

Short version about the project; it's a precast utility tunnel adjacent to the ocean for a Navy shipyard. Basically the government spec wants to spare no expense to ensure the concrete is the best concrete ever installed. We however would like to spare any expenses not needed. We fully expect we may need to bite the bullet but if there's shortcuts to equivalent results, or other tests people can suggest to demonstrate freeze-thaw resistance, please suggest them for JMack to run for us.

Ian Riley, PE, SE
Professional Engineer (ME, NH, VT, CT, MA, FL) Structural Engineer (IL)
American Concrete Industries

https://americanconcrete.com/

 

[JMackNH]

Small world!

Thanks for fleshing out the details - I'm curious to know what, if any, alternatives there are.

 

[TehMightyEngineer]

Might be none. The concrete specification alone is 31 pages; reach out to your contact at our company and they'll get you a copy of the relevant specification sections.

By my reading they're requiring we meet a minimum durability factor of 90 per method A of ASTM C666 at 300 cycles. By my understanding our project manager wants us to find alternatives to that.

My understanding is we need to create a mix design that meets this requirement. I don't know if we actually need testing right now, or later, or ever. So, maybe our PM is just looking for a way we can quickly test mixes such that we have confidence it will meet a rigorous ASTM C666 test. You'll want to bring that up with him as my understanding is limited as I didn't do much delegated design engineering on this project and thus was only loosely involved.

Ian Riley, PE, SE
Professional Engineer (ME, NH, VT, CT, MA, FL) Structural Engineer (IL)
American Concrete Industries

https://americanconcrete.com/

 

[JMackNH]

'Loosely involved' is a perfect way of describing my involvement, as well. My contact called to see if I've had any dealings with this spec. I read the ASTM standard and found a great youtube video detailing it and emailed a couple of engineers. At this point, I'm just putting out feelers to see if there is any info I can pass along. There is quite an investment in time between that required for designing the mix and then that for the actual testing.

 

[Ron]

Freeze-thaw testing is a pre-construction event so it has to be planned a bit ahead. The reason for at least 14 days of curing is to allow the concrete to gain sufficient strength and chemically hydrate enough of the mix water that you don't get inordinately low freeze-thaw resistance. C666 is the appropriate (and essentially the only) accepted standard for direct evaluation of a concrete mix for freeze-thaw resistance. There are numerous others such as for roofing tile, soil-cement, brick, block and others, but for concrete, it is the one.

 

[JMackNH]

Thanks Ron

Your assessment confirms what I've been reading and hearing so far.