What is fly ash, slag, and silica fume and why do we use them in concrete?

[@Indy0465]

I'm having a 10' x 20' concrete pad installed for a 12 ton Swim Spa, so I reached out to my cousin, Mike P in Maine for some guidance. His suggestions led me to do some more homework, which lead me to your video. As a facilitator myself, I was highly impressed with your ability to convey the science of concrete to someone with no background or education in concrete. Sincerely appreciate the knowledge!

[@abums3oud]

I am acivil engineer , your videos are great Regards from saudi arabia

[@jamesdonnelly8888]

What a great teacher. You have a lovely of investing energy into the education process. I wish all my children's teacher's were like you. Also love the passion you bring to your subject

[@nills2gills811]

One thing I like about your videos you don’t talk down to others for not yet understanding, like a kid is never mocked or ridiculed for not knowing the answer to something it makes you feel good to admit ignorance. Also very scientific, like what’s actually going on and the processes involved if we look inside the cement with a microscope? Because those little shapes low and behold are holding the whole thing together large aggregate down to the micro particles like a fractal pattern. You make learning exciting honestly while being technical yet fitting for beginners. Really well blended personality holds strong like a good concrete mix! Rock on brother B)

[@Chrisymcmb]

Dude, you're like an allstar concrete sensei.

[@rolandgonzales3343]

I love videos like this and thank you for taking the time. The narration and interest you have demonstrated here made it more accessible for the layman to think about. Thankyou for this. This is what I use the internet for.

[@leonardoborges6382]

I'm starting in the concrete business as a Batchmen and this was incredibly helpful. Thank you so much

[@sandipkumar1021]

I'm a flyash provider

[@dansimoneau2789]

This is an absolutely impressive video. Great teaching tool to some young project engineers in the construction business

[@aion2177]

Very good video 😊.. this channel is amazing. Contemplating what the world looks like when every domain of knowledge is covered in an easy to access form by an enthusiastic teacher. Im just a programmer which wants to pour a comcrete slab for my shop and i feel like a concrete ninja after watching your videos 😂😂😂

[@ericspda]

Tyler, these videos are exceptional. Would you be interested in making a video on the ‘best’ concrete possible for durability? What the approximate mixture would be, what additives would be used, the w/cm ratio, how it would be cured, etc? I was thinking about making a concrete bench that would be left outside in a cold climate, and I think it would be kinda cool to try and make it last hundreds of years. Probably post tensioned with stainless threaded rod.

[@TylerLey]

I like that idea. Let me think about it.

[@johanedduque]

Jon, you can try using one of my impermeable self-healing nano and micro reinforced concrete made from Waste to Energy Ash.

[@ndenise3460]

What about a combination of say type f fly ash and silica fume?

[@johanedduque]

@@ndenise3460 What about a concrete that is made with Waste where all the aggregates come from waste a concrete that is impermeable, self-heals and is photocatalytic... That is Ashcrete

[@jr3474]

what about organic ash as additive for concrete??

[@auliamuhardiarifin8427]

BEST VIRTUAL TEACHER

[@majjood02]

Great Video! very informative, easy to understand and directly to the point! looking forward to learn more about concrete with your videos.. Thanks Tyler!

[@marinaanddenisz9925]

Tyler, there is a cool new material called Poraver. These are nano glass spheres made of recycled glass in Germany and Canada: it is used as an admixture in concrete. As a result workability of concrete is amazing, and goodbye cracks, too. The resulting concrete is lighter, stronger and denser than without the rough glass beads.

[@anikac8380]

Pardon my goofy question, but have you any data on wood ash? I only ask because I first learned about fly ash in cement from an article by a DIY builder using wood ash as an additive to his cement. He referred to fly ash, and the ancient use of volcanic ash. Other question, of course, is how feasible is it to use volcanic ash? Since we know that works well, do we still have that recipe? (We still have pieces of the cake, we must certainly have the technology to reverse engineer the recipe.) There are volcanoes belching ash around the globe. Is that stuff valuable? Could be a modest supplemental income stream for some lucky volcano neighbor, if it could be Harvest it safely. Your videos make me curious about possibilities.

[@lesliesweeney368]

Awesome presentation tyler very informative well done thank you

[@jialin6174]

Good video, the explanation is very comprehensive, can learn a lot of knowledge

[@TylerLey]

Thanks so much.

[@VenturiLife]

It's such a science... I'm interested in the Silica fume and it's use in superstrong concretes. Excellent explanations.

[@TylerLey]

Thank you for the message! I agree that silica fume is a cool tool.

[@VenturiLife]

@@TylerLey Awesome info you're providing. So apparently, due to the huge increase in compressive strength using silica fume / fibres, they can use less re-bar and build with less material using it. Do you have a video on super-plasticizers also?

[@TylerLey]

Shades2 - Silica fume can help with this. It depends on what you need your structure to do. If your structure can allow slender members then silica fume is great. However, there are many members where strength is not the goal. Here is the water reducer video: kzbin.info/www/bejne/p5CzqI17apyGosU Thanks so much for watching and for your comment!!!

[@ROCKMAXBOARD]

@@TylerLey Master,I use silica fume to produce magnesium oxysulfate concrete. There are good aspects, anti-permeability,dimension stability increased, but strength decreased,it might be wrong way of mix slurry ,low speed mixer,time, etc, i don't know.Someone said,the best way is use fly ash mix with silica fume. I wish to increase durability of mganesium concrete,but do not scrafice lot of strength,is it possible?

[@garybrown9719]

Thank you for getting to the point

[@violettownmicroenterprises1528]

... even some women love concrete...yup ! love this guys knowledge sharing. An amazing material, looking forward to having my tiny above, workshop below build using concrete panels like kit-form. fast, indestructible, recyclable, energy efficiency equal to stick build with foam cores, great embodied energy.... and it looks great. Curious about the use of recycled fibre optic offcuts and the use of basalt reo.

[@atulsarang]

Nice production, thanks for sharing the info.

[@TylerLey]

Thank you!

[@carpenterfamily6198]

Would fly ash work well in an Aircrete foam mixture ?

[@jeffreyquinn3820]

I'm guessing you should really wear a HEPA filter around silica fume, then. I don't think short-term exposure is much of an issue, though.

[@michealdraconis6179]

If you were building in Alaska what type of concrete would you use ?

[@marisman]

Proper chemical densifiers provide reactive silica to the concrete mix to create that pozzolanic reaction. This is exactly what they do to create harder concrete surfaces.

[@sergeyshubin6679]

the best explanation

[@richardszyniszewski2791]

Hi Tyler, I watched many of your videos and I am amazed by your knowledge, but even more by your passion for concrete. I would love to get your input on the following subject. I need to a build a concrete wall behind the existing concrete reinforced 30 years old wall which is in a bad shape (with partially exposed rebars and many cavities) that is being constantly stricken by the sea waves. What type of concrete, rebars, admixtures, etc. would you recommend for the new wall. I hope you will read my message and respond to my inquiry. Regards,

[@bikerfirefarter7280]

you could try glass/polyester etc fibre reinforcement, or basalt fibre, or micro stainless steel fibre. plenty of vids on 'Net.

[@robertogzalez]

Thanks for the info Tyler!!

[@TylerLey]

Thanks Roberto!

[@nandanpatidar258]

Valuable information 👍 In my area fly ash comes from about 4 different sources and all of them look and feel different. Is there an easy way to determine whether a fly ash is class C or F without doing complex lab tests?

[@amanullahhabibi6278]

My king i love your lectures Allah (god) give best health and long life

[@cunninghamhome6971]

What are the particle size distribution for these SCMs? Can different size distributions be ordered? What is the performance differences due to different size distributions? Can the SCM be processed ( ground, fired, …) to alter the performance? Are there additives that enhance the performance of these SCMs?

[@HEMPPUBLISHINGCOM]

I love to pick people's brains, but yours? Wish I could sit down with you for one day, only riches will come our way. If not, thanks any way! I learned so much from you today..... Best wishes on life....

[@shettybh]

Good Work Tyler. Liked mos of your videos.

[@pulporock]

One of your best vids I have watched. What about meta kaolin, as another?

[@TylerLey]

Good question! I need to make a video about metakaolin. In the US metakaolin is only available in limited regions. I could also do one on natural pozzolans but they vary a lot between sources.

[@rpsoren]

Question, I was wondering about what if someone replaced all the products of concrete with similar sized (or smaller) recycled products. Like my idea is what if someone used say fly ash, slag, ground tires, ground plastic, ground styrofoam, ground glass, maybe even ground wood or wood ash, then mixed all those with hydraulic lime and water? Wouldnt that be more dense, workable, insulated and harder than concrete? And would you even have to have steel reinforced steel? I just don't know enough of the chemistry of each of those products if they would work well together, if it would be load bearing, what the thermal desity would be, if they would be toxic, or if they would just fall apart. I've recently been interested in how to used products that take a long time to biodegrade like glass, tires, plastic, styrofoam, fly ash and slag and make them into a workable product that would harden like concrete does. Can you give me any insight on if this would work or is it a pipe dream? I also thought about adding hemp Hurd to the mix but wanted to see if the non-biodegrable products would work first to fix the problem of waste in the world before adding any natural products for thermal insulation. I've been brainstorming like crazy about building a high thermal mass round home with a geodesic dome roof in the shape of an IMAX theater (tilted rotunda?). My brain has been on overdrive on how to make it with no concrete and only recycled products while also making it energy efficient and as low of cost as humanly possible. And it all starts with the footing which is where I came up with the original idea posted above! So that's where I'm at, any help or ideas would be greatly appreciated. Thanks Ryan Soren

[@0mon0zz]

Great video man you're amazing! Regards from Australia

[@jodymadoche]

Thank you!

[@TylerLey]

Thanks for watching!

[@michaelchua6494]

In absence of fly ash, is there other cheap alternative mixture that you can provide to concrete to make it stronger? I'm planning to mix it to make a stronger and durable hollow block...thanks

[@manopyro]

What's your thoughts on aircrete for building structures? Would any of these additives be beneficial?

[@MrAllan9]

Fly ash increases aircrete strength and flexibility.

[@فاروقحجام]

Is the silica product the same as silica sol?

[@johanedduque]

Tyler, thanks a lot for your vids.

[@TylerLey]

Thanks for watching!

[@johanedduque]

@@TylerLey Dear Tyler, thanks for replying. I make concretes with Waste to Energy Ash, pretty interesting concretes, they are light-weight, photocatalytic and are self-healing and are made with a waste byproduct, I'd like to know if you would like to make a vid about it.

[@हरिःव्योम]

So how do you really mix Silica Fume particles? what's the point if it all balls up?

[@JB10008d]

so how do we make sure this isn't in our concrete blocks at Lowes or Home Depot?

[@shaktisehgal9777]

Sir Can we add fly ash to m25 mixture in column casting & if yes, pls tell ratio n how much stronger it will make the column?

[@johnfajer7691]

You're badass, bro. Keep it up!

[@user-rv2tn9qx2b]

Bro what is the fly ash usage percentage now?

[@mariodinovo4018]

it makes readying suppliers richer

[@jenpsakiscousin4589]

Ash and slag can make the concrete strange to finish, especially when pumped. Maybe the plasticisers don’t play well with the fly ash?

[@mekka_awy]

Hi Tyler ! I have a q What is the difference between silica fume and fumed silica (white) ?

[@ndenise3460]

What studies have you done wrt using recycled glass aggregates?

[@TylerLey]

I have not done any but there are others that have.

[@marset.designsplus3813]

@@TylerLey can you recommend.? Links possibly?? Please....♥️🇹🇹

[@sabbirahmedsumon1023]

Hello, I'm from Bangladesh. I have question to ask, I have watched the whole video but still I want a confirmation. A cement distribution company in our country markets their cement as 'fly ash free' the tells people that fly ash is a floating element and it has no use in concrete. These are totally rubbish I know. But is it a good idea not to use fly ash and using slag and silica fume only? I mean what are the effects of using such concrete?

[@lefthandedhardright8839]

The correct title of this video. **Fly ash can be valuable garbage.**

[@mahmoudakef7499]

My graduation project is about geopolymer concrete we used fly ash with liquids like sodium silicate and sodium hydroxide but we didn't achieve any kind of slump or any strength the project just fails now we have just 1 and half month and we are in a very critical situation. My question for you is it okay to use silica fume instead of fly ash with these liquids or should i use water instead?

[@mahmoudakef7499]

The reason that the mix fails is that the flyash is not really fly ash we bought it from an unreliable source

[@zazugee]

is wood ash similar to coal's flyash? recently i was trying to extract use potash from burning garden's lefovers i tried biochar last year, but this time i wanted to recycle the K so i washed the ash and used the water for irigation but the lefover settling particles i collected them and dried them i'm intending to use them for making clay-sand bricks more resistant to water erosion

[@bikerfirefarter7280]

No, nothing like it. The K (and Na, Mg etc) will wash out as hydroxides, very alkaline, if left exposed to air they will gradually absorb CO2 to become less alkaline. If irrigating with them they can build up in the soil and 'salt' it if you don't irrigate/dose properly. The bio-char will have most of the minerals that would be in the ash anyway. the erosion resistance of the bricks depends mostly on the vitrification effects of the firing and/or if you chose to use the minerals K/Na etc to 'salt glaze' the bricks.

[@fieldlab4]

Have you talked about air entrainment and insulation characteristics? Just curious. I'd love for you to talk about mortars. Portland cement was the worst thing to ever happen to mortar, unfortunately. Lime mortars were far superior but unfortunately are hardly available today. Read about the repair of the Washington monument as a starting point.

[@TylerLey]

Thanks, I will check it out. I am working on a foamed concrete video. That may talk about the insulation.

[@apeacefulwolfretirement1984]

@@TylerLey i would like to be alert wend you publish this futur vidéo about aircreet and maybe your sugestion about the experiment of "Honey do carpenter"

[@bikerfirefarter7280]

hydrated lime is still available, with a bit of ingenuity you can still make lime mortars.

[@fieldlab4]

@@bikerfirefarter7280 I have made it that way for repointing old, soft brick. I just mixed mason sand with hydrated lime. It works great but takes weeks to set up. I introduced some portland cement to make it set a little faster but that defeats the purpose. If I recall, there used to be another form of lime like anhydrous or something that sets faster. Hydrated lime basically needs to dissolve naturally and rebond in order to set. That's the power of lime, that it's doing this all the time, it's self healing. With this method I think that self-healing is the only way that it sets up. Besides being self-healing, it doesn't shrink as it sets, causing all kinds of bonding failures, weakness and leaks in repair work. That's the other huge advantage of lime mortar, and the third crucial advantage is that it's softer than the material you are typically mortaring together. So it doesn't damage and fracture that material! Portland mortar is very hard and strong so people think they're doing a great job. Then when the old bricks fall apart and fracture because the mortar was so hard, they say "well the mortar was good but those old bricks just couldn't be saved", which is the exact opposite of the truth. Not only is Portland mortar hard and not self-healing, meaning it will eventually fracture and turn back to dust, but it shrinks as it sets so it actually places more stress on repaired areas, and then it doesn't allow settling and rehealing. It's basically a disaster for old soft brick or natural stone. And all of that is why they didn't use it to repoint the Washington Monument. I believe they went through a lot of work to research these issues and recreate an appropriate lime mortar. Either that or maybe they imported it from Italy.

[@bikerfirefarter7280]

@@fieldlab4 'lime mortar' is not just hydrated lime and sand. 'anhydrous lime' is calcium oxide, otherwise known as 'quick lime', very caustic. hydrated lime mortars, and most other cements fully cure through the years by adsorbing CO2 which reacting with the calcium (and alkali metals) become carbonates. Corporals Corner has a video on 'Roman concrete', that will point (scuse pun) you in the right direction. I have used 6:2:1 of sand: portland:hydrated-lime as a substitute for old school lime-mortar with good results. Plastering sand works well. Setting time is a little longer but acceptable. In places where setting time needed to be quicker various accelerators can be used. Small amounts of sodium silicates can be a useful additive. In outdoor situations I have also accelerated the setting by tenting the work with a tarp and putting a steel bucket full of charcoal under the tarp (one 12mm dia hole in the bottom of the bucket), light the charcoal FROM THE TOP to avoid CO, and when it's lit after 5-10 minutes to establish, put a fairly well fitting lid over the bucket (slate or stone etc) and put it under the tarp. The charcoal slowly burns overnight and the CO2 released rapidly hardens the exposed mortar (be careful of any carbon monoxide). see also. www.limetec.co.uk/limetec-lime-mortar-mix-ratio.html

[@cchemmes-seeseeart3948]

why is there no 'save' option under this video?

[@kannadanewscorner]

nice video,thank you !!(from india)

[@TylerLey]

Thank you!

[@nigerichapu1760]

under what conditions should fly ash and slag not be used?

[@nmrudolph]

PS we use Fly ash in the landfill waste industry because you are not allowed to put liquids in a landfill so they solidify it was fly ash. Hence why I’m watching to learn.

[@captainamazing1356]

I figured out a mix where my test sample is a quarter inch thick and in some places less, does NOT have any fibers or any reinforcement of any kind and yet I can't break it with my hands

[@benbradshawjr2856]

I work on older homes and you can tell a foundation that has slag mixed with concrete and an 80 yr old home that has faulty downspouts/ gutters,those foundations crumble easily.they saved money mixing slag with concrete but as longevity in my experience it doesnt last.i can post a pic of a concrete/slag foundation thats gone to crap at a hpuse im workin on tommorrow youd think about scimping on cement.i can post more foundations youd think twice it crumbles after time makin a useless foundation

[@jesseadamson1077]

Does anyone know what happens when you used expired flyash? And can you use it?

[@muskokagrind7396]

If I could custom design a mix for doing floors what would be the best mix design? We always tell them straight portland

[@MrSunrise-]

Use Hardcem from Cementec.

[@mohamedthasneem7327]

Thank you very much sir 👍👌👌

[@Wilber-WA]

Gracias 🙏

[@grizzlygrizzle]

very informative

[@cameronoverfield8764]

I love ur video!

[@zobaedjaber8971]

Please make video with subtitle At lust awesome

[@zidnyknight3611]

thankks

[@tobintempleman4372]

Man... I want to understand you and I'm going to have to research the terminology that you use.

[@kiranrampp19]

Nice one..!!

[@NuclearSavety]

... just a side note, it would be easier to understand when you would use standard chemical reaction nomenclature ... was confused why carbon monohydrate (CH) reacts with sulphur (S) forming caesium monohydrate CsH) ... ;-)

[@TylerLey]

Sorry, that is cement chemistry notation =). Most of the concrete people know it but I could see where it would be confusing.

[@theyuha]

What happens if you do not remove any cement but add fly ash?

[@TylerLey]

It creates more paste in the mixture. This can have lots of negative effects on the concrete.

[@valentineiloh8354]

@@TylerLey it can also be cost effective

[@ashwanisehrawat9239]

How can we reduce the retention of flyash when using in Readymix concrete plant, please any one who has the knowledge pass it to me, I really need it.

[@valentineiloh8354]

Possible by reducing your superplasticizer admixture dosage in the mix or by introducing Accelerating Admixture in your mix

[@maxwebster7572]

Did you see on This Old House that there are 30,000 + homes with bad foundations that are blowing out from minerals in the concrete?

[@TylerLey]

Yes, it is called pyhrotite attack. It is a big deal and there is not much you can do about it. =(

[@marset.designsplus3813]

Wow‼️so 😥

[@mitchyelvington4776]

but finishability is what i look for. what about the craftsman?

[@bubba9482]

Best finishability is straight cement, ask any artist, I mean cement finisher.

[@kokyk8018]

Anything this days are made to last very short time that's why they won't tell us wish secret form will last longer that's their purpose to keep saleing us more

[@dhirajmedhi1268]

Nice guy

[@EddieVBlueIsland]

Not quite accurate on the slag issue - lime or dolimite used in steelmaking - a basic slag - limestone is calcited into lime before use in steel industry - that is why the greenhouse religon object to because it liberts carbon dioxide.

[@cameronoverfield8764]

Let’s take all that shit back are batch plants don’t know what the fuck they are doing good video

[@cameronoverfield8764]

Fly ash goes to the oil field in big numbers

[@bobdillan2345]

dont ever call me a fucking concrete kitty again

[@homeroquinonez5178]

Fly ash sucks to finish, and moves around like jello when finishing and takes forever to dry, but that's what builders wantt cheap concrete and shitie work

[@milenkagrears621]

hello concrete kitties! LOL

[@marioxerxescastelancastro8019]

11:46 “We are using everybody else waste to make our products better” This is tree-hugger propaganda.

[@cameronoverfield8764]

It makes concrete sticky. Sorry man I don’t agree

[@bluekenya4825]

Great material combined with a horrible handwriting using a horrible pen color on horrible paper. Or I'm just a cranky old man.

[@matthewgill9893]

Concrete pornography.

[@007squirreldehne2]

where all this blah blah blah bulshit you're saying slag and fly ash is the worst when you're trying to polish the floor or stain it I wish they'd find something different or stop using it all together

[@TylerLey]

Thanks, Can you tell me more about your problems?

[@bubba9482]

@@TylerLey I think what he's trying to say is that fly ash and slag affect finishablility. Weather you're running a troweling machine, hand troweling or broom finish. I've never meet a finisher who said "I love fly ash". I understand the benefits it has, but ask any finisher and they'll tell you that straight mixes finish the best. In my region (Midwest), they typical fly ash dosage is 100 lbs.

[@nonyabuisness]

Remember... Fly ash is toxic

[@TylerLey]

Nonya - Not all fly ash is toxic. Furthermore, placing it in concrete is a great way to encapsulate it and get awesome benefits from it.

[@nonyabuisness]

Tyler Ley I use metakaolin a lot.

[@nonyabuisness]

In my overlays and countertops

[@TylerLey]

Metakaolin is great. It is pretty expensive in my region.

[@patkonelectric]

So were did the name 'fly' come from? Cuz the ash tends to fly away in the Wind?

[@amanullahhabibi6278]

My king i love your lectures Allah (god) give best health and long life