I've stumbled across this channel and can't stop watching this guy talk about concrete. He's a great teacher that makes even concrete interesting

Batch man here, and I’m feeling the love. Concrete science is so under appreciated.

I am doing masters in civil engineering and I really love how passionate you are about concrete. I have also got motivated.

I've tested concrete before I discovered that driving a mixer was easier and paid better. There was a field test for air content that involved a pump and a gauge. When I first started this comment I though I'd forgotten how that was done, but after a minute or two the memory came back. Tyler Lee, I have yet to fully explore your KZfaq content. Have you done any on the field testing of concrete, as well as everybody's favorite, the break test performed with a hydraulic press in the lab? When I was doing it we were using molten sulfur to cap the sample cylinders, which were much larger than those I've seen used now. I'm now retired. Do you remember the killdozer that terrorized Granby, Colorado? I hired as a driver for Mountain Parks Concrete as they were rebuilding the parts of the plant Marvin destroyed. I've delivered concrete at -12 F. Amazing how fast water freezes at that temperature, even with hot water in mix and tank. When I was working I did not think delivering ready-mix was all that great a job, but looking back it is probably the best job I ever had. Especially since I was delivering to places in Grand County, Colorado, one of the loveliest places on the planet. I could tell you tales of concrete abuse, usually involving adding water to the mix, contractors request, so the five inch slump becomes a more workable seven or eight. This was during a luxury resort and vacation house building boom. Some contractors wanted to place quality concrete that lasts. Many simply did not seem to give a shit about that.

This all seems like common sense to me I've worked Concrete in many forms from forming pouring and finishing to demoing demo is where you really get to know the strength of your concrete's and cement . The need to get it down and get it finished so it can be used is the problem . Does not allow for natural cure time . Gives reason for the chemical cures . I don't know if things have changed but my day I learned the hardest concrete known to man or ever found was it the very bottom center up dams that were not forced to cure quickly but allowed to cure naturally . The toughest and hardest concrete I ever had to demo was the oldest concrete I've ever seen the footings and peers of the oldest Factory building I've ever been in . So hard using the Jackhammer was useless had to drill and use a hydraulic Rock splitter to remove them . from what was now being used as a showroom in what had been used as a basement for many years but originally built as a cistern . My Mentor in concrete when I met him had been working concrete for over 50 years . I'm just about the age he was when I met him now . You have to share studies he had followed and everything he had learned . He'd always say with concrete everyday you learn something new and I have found that very true . Very much the sample taker and studier of our biggest pores didn't worry much about the little ones . Always talking about his studies on Research done of core of the oldest dams . always very controlling with the moisture content when pouring always watching that shoot to make sure the mixture is mixed evenly not too dry not too wet . also while finishing never stepping on till just right and then always adding water, simply splashing it on with an old never used for anything else but splashing water tar brush . out of the same clean 5 gallon bucket and 2 and 1/2 gallon buckets that he'd been using since before I knew him . always promoting the importance of using the cleanest clearest water in finishing or pouring or curing your concrete . always tented every pore with plastic and cured for at least a week . tending to it 2 to 3 a day soaking it down with water or keeping it from freezing but holding a good moisture content . the commercial industrial contractor we both work for was pretty adamant about using these practices at least in their own pores . in the contract jobs where if you don't get things done by a certain day you start paying for the job you're doing . in comes the need for the chemical quick fixes put simply make it more stressful and harder . and truly give more need for rebar . from my experience especially in demoing concrete you can easily see the less need for rebar when you increase the cure time . I truly believe and see that it is the calcium and lime deposits left behind by water molecules that solidify and hold and give strength to the concrete or mortar . Those peers and footers had no rebar and are the hardest concrete I've ever had to demo and remove. all the concrete I've ever demoed so much easier when it has rebar or mesh in it . I have even used a blunt old bit in the jackhammer on little spots of exposed rebar from jackhammering . given enough time by braiding that rebar you can tear a pretty big pad apart much quicker and easier and definitely if you can lift that pad and get air space under it it'll fall apart really fast . the Footers and Piers I keep referring to it was easy to see they were a three-part mixture of crushed stone no bigger than 1/2 inch sand and cement to this day I like to mix my own using pretty much the same X but if I can get foundry or fly ash to mix in the best thing I've ever seen happened to concrete ! the only concrete we ever removed that had rebar in it was an old concrete bank vault with walls two-and-a-half feet thick number 6 rebar vertically every 3 in and a checkerboard pattern with number five every 3 in horizontally tied to that . with a 3 foot thick tap done in the same pattern but with the number 5 and number 4 rebar . it must been a great sense of satisfaction to be on the form and poor of that one . we didn't really get to demo that one we hold it to the landfill though they had a subcontractor come in with a big wet saw that cut it into pieces that we could load and haul off and the landfill would accept . well the learning never stops and I could go on much longer but it's time for me to go . if you want to see concrete fall apart quickly pour it and backfill it with soil high in metal deposits especially iron . peace light loving gratitude freedom I hope everybody gets their free and joyous share of it all !!!!!!!!9 HHBpHhelps

I've never thought about concrete ever before starting to watch your videos.

Find a SO who looks at you like this guy looks at concrete. Seriously, though, great videos. You've got me learning by choice, and that's always the way to go.

Hey Tyler, I'm craaazy about watching your videos. If you're ever having a really crap day and you're thinking to yourself, " I wish I was making a difference in some dudes concrete life down in South Africa" .... meet "some dude" Just started my ACI Fundamentals in Concrete and have had a lot of questions which you've answered through your videos. Thank you, thank you. God bless.

I enjoy this as I have an interest in concrete. I met and did work for a gentleman years ago named Fred Oswald. He was in the business of manufacturing concrete vibrators, in fact I think he invented it, at least the backpack type of units that were being manufactured in L.I. New York.

I helped a Dam engineer build a bridge over a stream in New Mexico. He added a Ny-quil cup of a silicon substance he said was a by-product of the waste in growing silicon cylinders. One Ny-quil cup per 1/4 yard in our mixer. It added tiny air bubbles for freezing contraction and expanding. It was a beautiful bridge. It looked and acted just like a real bridge over a highway. it was beautiful. It held a convoy of cement mixer trucks and he poured a huge monolith slab for his mountain cabin. I wonder if the stream took it yet? its taken heavier ones but he didnt listen. Im gonna go check on that.

I know that they have the air but it is the first time it was told to me why.

I worked a concrete project where the spec was simply "All concrete shall be air entrained." I asked about the spec before concrete work started, citing the recommendations for the floor surface coating ("...air content not to exceed 3%..."). Never got a response. The Corps of Engineers inspector enforced the entrainment spec. When I tested one load and found 12.5% in an interior slab on grade, the C-of-E inspector said, "That's all right, as long as it has air." Later, when they were compacting the aggregate base for the parking lot, the contractor refused to use the vibratory function on the roller because "...when we turn the vibrator on, the slab cracks."

In the 80s I worked in the r&d labs at FEB, the company that produced the world's first concrete additive "FEBMIX ADMIX" (I think!). Tyler mentioned soap in the vid. NEVER USE DETERGENT IN CONCRETE!! You'll only get large bubbles (entrapped air), a proper admix will give small bubbles (entrained air). I still use the "magic mix" ...3.2.1. 3parts aggregate, 2parts sand, 1part cement and then the correct additive for the job.

Really good video. Now i can't stop thinking about the validation and acceptance of new prototypes of air entrained admixtures just based on the percentage of air increased or permeability reduction. We can go beyond with the available technology of our time. Thank you!

Air entrained concrete is desirable in tropical climate also? Very passionate video. Surely will get the concrete crews into the why’s too.

Excellent presentation. Thank you for educating us on some of the most important things that affect concrete durability and performance

I love the content and the delivery of the information. WONDERFUL. Thank you again.

I would love to see you do air Crete. I recently tried to make it with mixed results but am really excited about it's possabilities

Hey Tyler! Love your concrete enthusiasm. I'm studying civil engineering in Europe, which means I'm using the European codes for concrete, do you know anything about them? If you do, could you do a video explaining some of the most important differences between American and European standards (except trivial things like the units)? And maybe which ones you think are better?

Good job👋👍 I watched your video that my lecturer suggested it. l liked so much😅😁👌 i will watch your other videos😁 i study civil engineering in turkey this year is my last year at the university..😅😊🙃

I love Concrete. I work Concrete. I live concrete. Great video, my friend.

Thoroughly enjoyed this . Did not know there was so much to concrete .

Your passion for concrete is really unmatchable Dr Ley. Thank you for sharing it with us.Sir,aerated concrete blocks are being used in my city a lot, recently it's being reported that these blocks are cracking along the edges quite often.The weather conditions are quite hot and humid at most times​ of the year.What could be the reason?

Not all concrete is the same though - it depends on the specific purpose that it's used for. I think it's worth to make some deeper studies in the area of concrete and various mix types. Sometimes you want a hard solid surface with a much lighter fill between the surfaces for improved insulation or weight reduction. Much like bones in a skeleton - hard on the outside but a truss work on the inside.

Loved the energy and style 😁

We build power poles from concrete - where the concrete is responsible for the dynamic loads of cabling systems. It also stands up against the freeze thaw process, and cars hitting them. There's a concrete testing regime at play when the batch is manufactured. It's got to be right - or it's rejected. On an unrelated note - my driveway is pretty good and strong these days :)

Thanks again and again. I am always waiting for your vedios.

Tyler is the best

Next, how to create only tiny bubbles in the first place: The bubble machine for concrete.

In sweden They take out the Bubbles to make it stronger by adding a little Dish washing liquid

it's a litte bit hard for me to grasp this concept, especially the graphs part. wahtever I am watching your videos regularly. Thankyou Sir.

Somewhere in an MTO spec or contract I read “xx% air entrainment minimum, entrapped air is not allowed” or something to that tune. The larger bugles are what they defined as Entrapped air, or air that contributes little to the F/T durability. Just something to help y’all remember!

I love your videos Tyler. Keep up the awesome work. I think science is the key to the future of our concrete industry. With that being said. I would have to say Portland cement was better in the 1950s. We did not need air added to it back then. Or did we and no one told us about it? Well I mean back in the day. You did not ask for it from the ready mix company's. When I was a kid. My dad use to hand mix concrete using Portland cement bags he bought. Along with a pile of sand and gravel. I visit these structures and slabs still to this day. They are holding up just fine. I don't think a bag of Portland cement is what it use to be. They changed the recipe. I think they changed Portland cement during the 70's & 80's. Probably changing it still to this day. I know the admixtures are giving us greater possibility's then ever before. I am all for them. Can we ever get that recipe back from the old days? Is1950s Portland cement not practical anymore? This kind of reminds me of an old song "Someone left a cake out in the rain. By ‘MacArthur Park". I sure do miss that Portland cement from way back when :-( . But I know it is time for bigger and better things now. You are definitely an inspiration to the concrete industry.

That means you need a powerful whisker or whatever you call it in your trade, since it brake up big bubbles and distribute it equally.

Hi Tyler, I accept your explanation, but please explain why vibrating concrete is so important in removing bubbles and helping it to move into voids. I do understand that it needs vibration with a concrete poker, but not over-vibrating. How does this fit with the information that you have presented here? Kind regards, Lee

Fantastic information!! I'm a residential contractor who occasionally does concrete. Read everything about concrete I could get my hands on 20+ years ago when I started but haven't learned much about the science since. How are the bubbles entrained in the concrete? By mechanical mixing at the plant or in the truck? With admixtures? A combination of both? Will too much mixing or agitation either in the truck or in the forms with a vibrator cause loss of bubbles? How do I make sure the concrete supplier has put good, small bubbles in the concrete? Thank you for making these vids, SO very helpful!

you saved my grades, thank you

An excellent ancient example of the value of air in concrete is the free standing round domed with central oculus temple in Rome known as The Pantheon. It was built with concrete, but in 120 AD the engineers knew the concrete would be too heavy to be free standing. It would collapse under it's own weight. Their solution was to add air bubbles to the mix, certainly not for the engineering reasons which you illuminate and likely more and larger air bubbles than would be done today but hey, 2000 years later it's still standing!

Plz discuss type of different types of concrete.

Aerated concrete block or aerated autoclaved concrete block autoclave block cost more but if you can make at home your own aerated concrete blocks you can build a home that has a r-value of 20 to 50 the concrete is also waterproof fireproof and soundproof it's the best building material for the new mini ice Age approaching

What techniques are there to ensure you have smaller air bubbles?

Great videos. If your knowledge extends to precision grout I'd love a video on that too, especially dry pack.

sir . plz make video on freezing and thowing effect.

thanks mr tyler !!

Romans were pretty good with concrete 2K years ago. Ask yourself this - why are many old Roman concrete structures still standing, and yet there are abundant examples of modern concrete failures?

Ley et al 2017 - Nice work!

Hi. Thanks for your work. Can you please make a video on how concrete effects the environment and how can we recycle concrete? Many Thanks

EXCELLENT

Thanks

My take on this is that the approved design mixes should include testing to confirm they get an appropriate bubble size and distribution that aligns with the aci charts for air content. I currently don't see any of the major labs in the nyc area doing that during mix design and I get to see almost all there mixes on a regular basis. Is this astm test for air content distribution/size typically being conducted after problems are observed like in a forensic arena or is it actually required for mix design codes.

Humm. What about the tropics? No freeze thaw there. So other criteria must apply. And we don't know about the compression strength of aircrete which I want to use to build my basaltic rebar reinforced dome.

for coastal construction.. in florida what kind of rebar would you suggest for columns and beams and walls? i see galvanized is just 10% more would you recommend it

Can you explain about ASR test in detail

Can you put polystyrene balls in concrete to create circular holes within the concrete when it sets? I was thinking how a bridge is strong if it has the arch because of the way the weight travels down the arch sides removing the problem of weight just pressing onto the top...if you know what I mean? And if this is a good idea is it better to have a larger or smaller polystyrene ball size? And also would they be better used dry, kind of sprinkled on a layer of wet concrete with the next layer quickly poured on top? Or better to mix them into the cement? (I don't know why but I am so fascinated by cement! Amazing stuff!)

No mention of the super air meter? My understanding is that it measures the quality of the air bubbles in addition to the entrainment.

Years ago I was at a resort in FL. The swimming pool apron was wide concrete and had lots of recliners. What was very strange was despite the brilliant sun, the concrete remained cool! It was almost disturbing. You put your bare foot out and life experience told me "your foot is about to sizzle...", but no - it was cool to the touch. How did they do that? My best guess was they injected the mix with air, but that was only a guess. Any clue?

How can I add small bubbles with the commercial 60 lb bags of concrete?

Sounds like a job for Fourier analysis!

Thanks for the classes. Do you also teach how to read rebar drawings?

How do you place small bubbles in concrete? What do you think about aircrete or is it beneath your contemplation?

If we v8brate it at a certain frequency? Could we achieve a spacing factor to spec?

Sooooo - the so-called AirCrete is a real thing? And a good thing?

Thank you for your information sir but does it effect the compressive strength of concrete?

So how do you create the different sized bubbles? The only reason I watched this.

Thanks for this video :-) You can also tell something about capillary absorpion by concrete with air bubbles, please? What are possibilities of use this type of concrete for foundations...

When is concrete looking material not called concrete? What is it, specifically? For example, does water + Portland cement + air bubbles (aircrete) = concrete? If geopolymers are the binder, is that concrete?

You spoke to us today at engineering camp search Kort Stuever for my channel

How do we only make tiny bubbles?

This may sound like a stupid girly question but I suddenly thought about it and want to know....what would happen if you whisked egg white up and folded it into concrete? I know I could test that theory but I am hoping someone can just tell me. Although it would probably cost a fortune...I don't know how much it would take. Just fascinated with concrete! It's such fun stuff!

Lov from india..

Where do water pockets came?

Tyler, how about your thoughts on aircrete and it's applications? Would love to hear?

Hi Tyler, my concrete is hissing like cricket bugs. Does this means that it has small or big pores? It is 8 weeks old. Once I splash it with watter I can hear the hissing and see previously not seen (when it was dry) capillaries like spider web... Will it help if I put sealent on top of it. We are near Canada border and winters can get decently cold.

Hello Tyler really great videos! I am trying to cast cement mortar in a wooden mold. The shape I want to achieve consist of 2 walls of 30 cm height and 15mm width. The shape's top view is like a capital T with the difference that the horizontal line (wall 1)is twice the length of the vertical line(wall 2). Now on the vertical line there is a rectangular block of 2cm (height_)x 10cm(width) that is screwed 10 cm above the base level of the mold which as stated earlier, is 30 cm tall. This will create a groove that will allow me to slide on a wooden shelf. In my mortar The ratio I use is 6 Portland cement, 5 blond washed sea sand, 0.25 Fiber glass fibers, 0.5 sika latex, 2.5 water. When filled, the mold is air sealed with a plastic bag and covered with a blanket. Demolding happens 36 hours after filling. 1) How does a mold that is thin, tall and encloses the cement mortar can affect the curing? There are narrow openings on the top to fill it in. 2 openings of 10cm length x 1.5cm width on the top of the horizontal line.(One on the left and one on the right side) and 1 opening of 10cmx 1.5cm on the vertical line. The rest of the mold is fully enclosed. 2) I use birch plywood that consists of exterior use adhesive for bonding the layers. Is this material ok for such a size and shape? Will varnishing the wood and sealing the sides with silicone used for windows help? Some vaseline is used and so far there are no issues with demolding 3)To fill in the mold, since there is no visibility to where the mortar has easily traveled to, shaking and vibrating the tabletop is necessary to fill it. How could excessive shaking affect such cast? And if possible define excessive shaking 4) Is there a way to eliminate the cracks that appear next to the desired groove? 5) The edges of the cast after it has been cured are a bit brittle and feel like a cookie when cut in half. Is this an indication of a sort and if yes what sort of indication (mortar, curing, liquid amount) I am really struggling to make this work well and have a smooth finish If I can send you images please let me know how I could reach you! Thank you so much Tyler!

Why don't you answer questions in the comment section? You even say to leave comments below. I'll ask anyway. Why is it that the concrete poured over 100 years ago is still there but if you pour concrete these days you can stand there any literally watch it crack and fall apart? And those holes? Up north here if you don't fill them in they'll catch water and freeze and bust up the concrete.

Finishing mud with high air con. Sucks .

Is modern day air ad-mix like a surfactant? Every mixer driver should keep at least 20oz of air in the truck if there is no company QC on the job they can always call with job specs yards in the drum and if water has already been added or needs to be added. As you know water added is a factor in air percentage

Tyler... is it correct to believe that the greater the impermeability of the concrete the less the need for air entraining? And, the greater the permeability, the greater the need for air entraining? If this is true is there a relationship between impermeability and compressive strength? Density? I have the idea, please correct it if I am wrong, that the greater the compressive strength (or is it density?) the less effective/useful/needed a PRAH like Kryton KIM is?

Roman concrete had volcanic ash and or ground up sea shells, I wonder if this had anything to do with entraining concrete, perhaps near perfectly.

Hi! I am looking for the way to make irregular natural bubble textured concrete to make the candle bottom! But I am frustrating because this is so new world to me. Can you help me with this? I want to make self-rising bubble concrete when I pour water in to the mixture. (I saw this in someone's video) But I don't know how! Then I found AAC concrete , can you tell me how can I make this at home using the materials like cement, lime?, calcium hydroxide, etc. ( I saw this ingredients in somewhere) Thanks

How do you control the bubble size and volume? By small orifices at the injection nozzle?

Why do we need air bubles in concrte?... They help in achieving (concrete dimensional stability, durability, mechanical performance, and flowability)

So AirCrete is the best? What ratio do u recommend? 8 parts of air to 1 part of concrete? Thx

Sounds like you are looking for the correct ratio of bubbles, vs permeability vs durability. A patent solution like that could be worth big bucks. Probably incorporate existing patents too. Doing the red tape maybe harder then invention. Not clear to me if the industry knows what it wants, just does not how to get there or if it is anyone's guess what they need. I don't know the size of bubbles or density wanted.

I wish the Illinois DOT would open their eyes and see this

Question: if I’m pouring a chimney crown and I’m using a bags of quikcrete, do those come pre-air entrained or would I be recommended to air entrain it. If so, how is this done?

I can't believe I watched a whole video about air pockets in concrete

Today we ported concrete and the boss was pissed cus mixer put air and the end of the day looks like crap

I would love to see what makes the concrete that was made by the Romans last so incredibly long.

Wouldn't the bubbles also be full of water?

I have difficulty understanding the accent... may i request if u could add some subtitles? Heheheh anyways i love your videos, it help me as an Engineering student. With love from 🇵🇭

Haven't read all of the comments, but, can you nor just use micro spheres to solve this problem? If a large sphere is needed, ok small ok. Can we pour a mix then implant what we want? I have a few other concerns..

That's awesome but I live in Brazil, I will never see concrete freezing.

Thank you Ley for the wonderful explanation. I would suggest the musical background should be removed it is irritating

8:05 Nice work! Is there link to that 2017 paper?

how about adding microscopic airjel

Thanks for your interesting videos my name is marouan from Morocco .do you have some studies on fiber glass AR alkaline resistant? If you can give me your opinion thanks

Imagine existing and obsessing over concrete simultaneously

Are the air meters, they use on building sites , accurate ?

I have a road building background. While building my shop in the backyard I poured the slab myself w/felt board expansion joints every 8ft horizontal and vertical. It still cracked & failed in my opinion. I was told this happened cuz I compacted the base. I used Lyme treated ABC and processed it like I was building a road. Does this sound right? Shouldn't the expansion joints been enough for expansion? I was told it needs to be able to expand into base. Thus my compaction of base is the culprit. Luckily I hadn't started the structure yet so I will be doing it again.