I am a recent member, so hope my response is not too late for you. I have had some experience with ASTM fly ash (Class F - not Class C) as a replacement for a high percentage of the portland cement in concrete (up to 56% by volume). As you no doubt know, it is a by-product of certain types of coal burning (usually in electrical generation), and is collected in the stack by electrostatic precipitators. As a pozzolan, its qualities are excellent for many applications, but you must understand how it affects the workability of the mix before charging ahead and using it. Is this what you were thinking of using it for? If so, I'll reply next post. As for suppliers in Texas, I cannot help you. Sorry. Try cement manufacturers or your state concrete association. It should be available, because it is such a beneficial product - even if it is trucked in. Good luck!
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