Great video! As always, thank you for your honesty and talking about the topics that are truly relevant in our industry. Keep it up!

@IntelligentConcrete

3 жыл бұрын

Thanks love!!!

Yes! We got hit with a harsh reality when the field-trial concrete showed up with slag instead of fly ash, because suddenly there is no fly ash. Big difference. Fly ash lubricates. Slag is continuously thirsty. We had been relying on a high dose of fly ash to make our 3D-admix method work. And learned a tough lesson - need to tweak formula again - to make adjustments for no fly ash. Seems that the bottom line is higher w/b.

@IntelligentConcrete

3 жыл бұрын

Thanks for the insight!

Harsh realities for sure. However, the SEFA Group in the Carolinas has 3 flyash reclaimation sites that beneficiate pond and landfill ash! The quality is excellent and should supply NC/SC for 12 years. The material cost is $40-$50/ton. However, it does have an end date.

Add that after the year 2000, each cement plant was required by the EPA to begin moving towards capturing flue gases. Part of this process re-introduces CKD (cement kiln dust) back into the cement processing, which in turn has increased the alkalinity of the cement. It is apparently this process is now essentially complete since in January 2019, the concrete industry announced that low-alkali cement will no longer be offered: Translation: there is no more low-alkali cement. This does not dramatically affect the initial properties of concrete, but it does introduce other challenges that have not been addressed and likely won't be by the concrete industry since their requirements are still being met, even as these changes present numerous challenges for those who coat, cover concrete; while adding unpredictable complications to long-term durability PLUS we are running out of quality aggregate, which amplifies these challenges.

@IntelligentConcrete

2 жыл бұрын

Well said!!! Mic drop!!!

@roberthiggins986

2 жыл бұрын

@@IntelligentConcrete OK...that made me laugh! Thanks!

Hey John, would you be interested in cross promoting channels? I need to have samples of Aircrete and other concrete designs tested this year for my KZread channel. If so how do I get the containers for samples?

@IntelligentConcrete

3 жыл бұрын

Can do Harry!!! Reach out to us via our website www.intelligent-concrete.com/contact-us/

We have customers that feel the same way, which is why they are all switching to zeolite. EDIT: It costs less than a traditional natural pozzolan, but more than fly ash.

@IntelligentConcrete

3 жыл бұрын

Awesome!

Hi Dr Jon, is this going to be a global issue? Imagine the cost of replacement pozzolans in Australia if alternatives need to be shipped all the way down here.

@IntelligentConcrete

3 жыл бұрын

Yes Sir. Going to renewable energies is a global effort. India and China will have some reserves but eventually...

@Ilove3SGTE

3 жыл бұрын

What would be the purpose of importing it? At that point wouldn't there be better methods of getting similar results?

@MrMickteen

3 жыл бұрын

@@Ilove3SGTE construction innovation is very slow in Oz. And very expensive. We get shafted on prices for all new technologies.

What about thermal beneficiation of ash ponds and landfills?

@IntelligentConcrete

3 жыл бұрын

Howdy Jabels. Nothing wrong with that to make a product but it will have a energy (carbon) cost as well as a financial cost for the benefiting. My point is there is no replacement for Class F Fly Ash.

It's not even about renewables. What has made the shift for us here in FL has been the abundance of cheap natural gas from the fracking boom. Pipelines from holes in the ground sure beats mining and coal trains from across the country.

@IntelligentConcrete

3 жыл бұрын

Well said deyc3!!!

How are natural pozzolans going to compete with cement? Sure, there are projects that will require something for ASR mitigation, but most fly ash in my area is used to reduce the cost of the concrete. No one is going to pay more for a natural pozzolan that has higher water demand than a straight cement mix... especially when they are not considering service life.

@IntelligentConcrete

3 жыл бұрын

Well said Heath!!!! Cost of the material and impact on fresh properties is our biggest hurdle with Fly Ash replacements. There is a group on ACI working on cement replacements but that was not a topic covered in this video.

@FOURSTAR50

3 жыл бұрын

Said perfect !!! Our plant it's about cost with management unless it's a bridge sustainability?? Any non DOT plants bahhaahahabahbabbha !!! Money bottomline...

@IntelligentConcrete

3 жыл бұрын

Boooooooom!!!

Fly ash of any type, not just F ash, will be dead. The local plants in my region will be converted to natural gas in the next 5 years. That is if they are still running, since they now shut down for economic reasons at anytime without warning. Alternative materials? Engineers still have a hard time accepting fly ash, so how will they react with local pozzolanic materials?

@IntelligentConcrete

3 жыл бұрын

The right questions to ask Lance!!! I’ll be chatting with some Engineers on our podcast about these very concerns and questions.

This is very true the Ready-Mix supplier that I get most of my concrete from their local batch plant here they are switching to slag instead of fly ash they say it is because they call for it in the highway mix designs now. the other company that I order from sometimes I grew up finishing there concrete and it is slag mix. After finishing flyash concrete for the last 2 yrs I like it better seems like less cracking than the slag mix and consolidates a lot better. They will still offer fly ash out of there other plant about 45 min north but I figured they will switch to slag there soon also. Is a 100 percent cement mix stronger than a flyash mix? I have a 40x80 shop slab to do next week and they won't have slag ready yet. I did a sm job yesterday with it and it definitely sets faster.

@FOURSTAR50

3 жыл бұрын

Keep the slump at 5" with a HRWR I know it sounds so basic but it's the absolute truth all the slabs I deliver to are wet !!! always wet get a pump bring on more guys take your time all the admixtures in the world aren't going to do anything when it's wet I can't even remember how many slabs I've poured not placed a 10+ in slump some didn't even have a slump (scc) just piss wet is what I would tell the next driver absolute piss ---- load separation

@IntelligentConcrete

3 жыл бұрын

Howdy Bryan, I apologize for the delay. What 4STAR50 said is true. Yes, 100% cement mix will normally be stronger than a flash mix, at least early age. Slag has a tendency of reducing time to reach initial and final set times and the fly ash (Class F Fly Ash) should delay those set times.

Do anyone need Fly ash I’m from India and can export it for you

@IntelligentConcrete

Жыл бұрын

Plenty of folks out here need F Ash.

@user-rv2tn9qx2b

Жыл бұрын

@@IntelligentConcrete how can I get to you

Time for engineered SCMs :)

@IntelligentConcrete

3 жыл бұрын

Well said!!!