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Check out: http://www.igga.net/

I would also like to know where the bridge is - this sounds more like alkali-aggregate reactivity.

Check out: http://www.igga.net/

Are you using a true vapor barrier or is this just 6 mil poly? Poly reduces vapor transmission about the extent a well-cured 3000 psi concrete mix will. In a situation such as this, where there will be floor coverings, materials stored in contact with the floor, a proper asphalt impregnated...

Cold-in-place will cure all your cracking problems. Foamed asphalt is even better, as it cures more rapidly and allows the immediate placement of the asphalt overlay. the pulverizing of the old asphalt and a portion of the aggregate base will remove all of the cracking, and reduce the...

UPDATE: Thanks for asking about the study. The original study was conducted (I believe) for the World Bank) about 25 years ago, and one of the researchers (Zaniewski) repeated the work for FHWA. That was published as well by PCA. A more recent study was completed by the National Research Coun...

For the design of concrete slabs-on-grade with and without reinforcement, for any and all types of loadings, for expansive and "normal" soils - refer to Designing Floor Slabs on Grade: Step-By-Step Procedures, Sample Solutions, and Commentary by Ringo and Anderson from Aberdeen Press and Amazon.

Yes, there is a bond test or pull-off test for concrete coatings.; Check with ASTM - I can't remember the number, it was 25 years ago when I built my first CANDU reactor and we were testing epoxy liners. You coat the concrete sample, score the coating and concrete with a 2" diamond drill bit...

As most of my experience is in roads, I have to say that the use of in-situ testing is a great tool for compliance testing, but a poor tool for performance testing. I always try to get my clients to insist on proofrolling roads and parking lots, and after each layer if possible. I tend to roll...

I don't know of a specific study involving rolling resistance vs soil types, but there was a World Bank study that examined rolling res. for trucks on asphalt, concrete and gravel surfaces. It showed that there was adistinct savings in energy consumption as the surface became more rigid. The...

The temperatures that you describe will generally have an effect only in the early ages of the concrete, and only while there is still moisture present in the concrete. The temperature will cause the concrete temperature to rise to the boiling point of the water in the concrete and eventually...

Hey Ron - if you read my post you will see: "And of course, the addition of slag, fly ash and or silica fume will all have an effect on the rate of strength gain." Slagging my post will not get you points! My comment regarding rate of strength gain is based on "cement" not...

I was involved in an economic study about 10 years ago regarding various types of construction for parking garages. Even with only one local precaster (no competition), the most cost-effective system, taking into consideration ease of construction, quality, low maintenance (in a freeze-thaw...

I would be very cautious of applying the 65% estimation factor these days. I don't know where your get your cement, but the powders today are ground so finely that it is more likely that you are getting as much as 95% of the 28 day strength at 7 days. Many of these estimations are based on...

http://hotmix.ce.washington.edu/wsdot_web/Modules/04_design_parameters/04-2_body.htm#k

Sorry! Yes, I meant a structural coefficient of 0.11 using the AASHTO design methodology. I would be interested in hearing what others use as coefficients for other recycled materials (rubblized concrete, for example) and for expanded asphalt. As the modulus of expanded asphalt increases over...

I have used millings as a base for asphalt concrete pavement in Northern Ontario, for roads carrying logging trucks. When aggregate sources are few and far between, you tend to make use of every resource. We used a conservative structural coefficient for the millings of 11. After...

Almost 7 months after the fact, I have to contribute this: CSA statese very clearly that the reason for casting and testing concrete cylinders is to determine the quality of the concrete AS-DELIVERED. The cylinders are NOT indicative of the concrete in-situ because of the differences in...

Check out http://www.usace.army.mil/inet/usace-docs/eng-manuals/cecw.htm and download the pdf file for EM 1110-1-1905. Table 4-8 is what I was looking for, and confirms/agrees with other sources. This table is for spread footings, rather than floor slabs, and the article provides guidance for...

Why does fly ash "eat" air entrainment? Specifications for supplementary cementing materials such as fly ash limit the carbon content of the ash, because it is the carbon content that reduces the effectiveness of the air entraining admixture. Fly ash is produced in coal burning power...