The silent killer of concrete! | Intro to Alkali Aggregate Reaction

[@DavidCaldwell1]

Never seen so much passion about concrete. Great video. Really interesting

[@TylerLey]

Thanks David!!!

[@MitzvosGolem1]

The Jim Carey of Engineering. Jerry Lewis of Concrete...(no insult intended just good instruction not boring) Excellent shows. Thanks

[@damianaranguren6736]

YOu the coolest Concrete Master King ever Tyler! Thanks for sharing your decades of knowledge in this amazing fun engaging way.

[@bryanwelton1442]

Wow I can learn so much from your vids and the more I can learn the better I will understand how to do my job the best possible way with research and knowledge from people like yourself thanks tyler

[@rafaelcdionisio]

Amazing informative videos with a simple language, thanks for the great work Tyler!

[@MauiXoXo]

This is deep& thorough explanation about CONCRETE CA.

[@naheedhaidary]

it takes a half hour for my professor to explain it. Thank you and hopefully I got a question about this in the test HAHAHA

[@EddieVBlueIsland]

Good explation - I love metals and also concrete.

[@vjaceslavsverdins5174]

That was AWESOME!

[@AdrianaGarcia-ql1ct]

I love your videos and the passion for concrete. New fan.

[@chinthapathirana6208]

Great work. Thank you.

[@shawlork]

Thanks for teaching me how to make an awesome septic tank

[@eeesss9593]

Loved your way of presenting the video. Thank you man

[@TylerLey]

Thank you so much!

[@majjood02]

awesome video! a simple and interesting introduction to the topic! Thanks Tyler!

[@bharatithakur8039]

Amazingly explained

[@marcredgate7288]

This is a great description of the problem, but how do we prevent or mitigate it?

[@rochrich1223]

Asbestos reinforced concrete became popular during WWII and stopped being popular during the 1950s when the walls started falling down. I worked in an industrial park that the new section was abandoned and the 1916 section was as solid as ever.

[@judeluhrs9741]

a kid in my High School Chemistry class last year said he "didn't need to know" what i was teaching ... because he planned to take over the family Concrete Construction Company one day

[@ravipatel5456]

I really appreciate you for that kind of knowledge sharing ..... Keep it up.....

[@CivilTreee]

Thanks a lot for your contents

[@stevenbiars6212]

This is fascinating. I wish I could afford to go back to school.

[@TylerLey]

Thanks Steven! It would be great to have you in class.

[@egwanworben2972]

Am working on waste glass as partial replacement of fines in self compacting concrete blended with silica fumes. My challenge is how do I reduce or avoid ASR in d research work.

[@sheratongallacher5318]

What causes it. Alkalis are dissolved in the pore solution They are often from cement impurities that go into the manufacturing from the fuel heating the flame making the clinker

[@cchemmes2096]

I'm trying to figure out concrete as a sculpture material, which lends a desire for greater permanence than replaceable structures like sidewalk or a driveway. I guess their is ancient concrete made so well it is still in existence, yet I hear videos like this, which speak of great threat. How do I figure out the best concrete mortar mix/ admixtures/ aggregate/ sealant/ method for such purposes? Is there any way to make concrete work as a sculpture material?

[@sotiriseliades7121]

Bro do you have a book with all of this knowledge? Let me know if you have, i am really excited with your knowledge

[@MahmoodXulio]

Same issue I had in my previous project, sodium chloride, polyaluminium chloride, PFAS and electro chemical process, but it was sabotage. How I can share with you some pictures!???

[@patrickp6775]

Great videos, thank you. Do you have one on how cement is manufactured?

[@lethaldriver]

concrete is said to develop much of its strength within 28 days. what if the concrete is neutralized with acid to lower the pH before the alkali can start doing damage? perhaps at one year or more, the concrete has developed enough strength and so its pH level can be lowered or neutralized with constant exposure to water or a weak acid.

[@mukulbhattarai5398]

Hi, Professor Ley. For a (RCC Framed Structure) house built about 8-9 years ago. There are some places where cracks appear right under the beam at junction of brickwall & beam. The crack is big enough to insert the tip of a pinky finger. The crack can be seen from both sides of the wall. What could be the possible reason?

[@bryanhiebert1]

Do you have any videos on suphate attack? I was looking through but didn't see any.

[@FufuFang]

This is happening to my university's buildings from the 60s, apparently.

[@dewiz9596]

Wow! This is beyond my understanding. So, I suspect that it will be difficult for most. More videos required. . . at a slower pace. Just a suggestion from a “not completely stupid”. . .

[@theyuha]

Does fly ash reduce the alkali reaction with silica aggregates? Silica is usually like quartzite, quartz, jasper, and other hard minerals found in glacial till. is this problem more of an issue with self mixed concrete? Moisture is the catalyst for the reaction, right? The truck cement should have this engineered into their mix by adding fly ash in the proper quantity.

[@lesliesweeney368]

What mix would cause this! And which wouldn't

[@asifthevamp]

Good work SIR...thank you so much :)

[@TylerLey]

Thank you!!!

[@craigkeller]

Watching my maps. Oh boy.

[@iiiheartt333]

@TylerLet My moms cement guy used water from the pool with fresh chlorine and acid added a few days ago to mix his cement to seal the grout lines around the pools trim that connects to the ground we walk on. Will that eventually break down the grout cement structure?

[@johnpeterson7264]

Great video ! Isn’t this at least a theoretical reason to not use rocks in our concrete ?

[@feder13]

Getting started, so.. if we are not using rocks, whata are the alternatives? thanks a lot!

[@yaser2000m]

by this way , can we use silica (quartz) as aggregate, I studied some where that only amorphous silica can do this reaction , and we can use inert quartz, is that true ?

[@matthewcalifana488]

How about using mortor to fix damage in the basement / cure menthed ?

[@lesliesweeney368]

Your making it sound like were still doing this.

[@jameslynch8466]

Hi Tyler. Please could you tell me does an increase in slab thickness help stop cracking? Be great to hear an engineer's opinion. Just discovered your channel and really enjoy your videos. Thanks for sharing.

[@TylerLey]

James - Thanks for the message. It depends on what is causing the cracking. Can you give me some more information?

[@EngineerPEretired]

Tyler, here is round 2 of the video below... enjoy the add-on --- It is a follow up at the same location, hope you can use the data that it is 16 months later and no ASR has changed on the interior side of that column base... Yet, a lot of ASR is showing on the floor, inside the breezeway... kzbin.info/www/bejne/gXS9dKJ-l6qWo6s

[@larrytinnin3357]

Will have to much water in the mix cause this type of cracking?

[@michaelcarson9688]

Hmmm... would this also cause surface popping?

[@muricamarine9473]

So is there any other form of making cement?

[@huda90]

How can we test Alkali carbonate reaction ?

[@poldasdinesh947]

For building construction purpose ....i had done PCC...one load RMC mixture was to worse...because 6PCC Footings are not set for 2days...what will be the reason behind it...in future that will any problem for structure...after setting also it seems very bad...just hitting with hammer on PCC..it is forming a small hole..on that we can go for footings..or not..

[@TylerLey]

Sorry, Poldas but I need more information. Good luck with your project.

[@jonpig1]

Can you speak about semi-dry or zero slump concrete for block or paver production?

[@TylerLey]

Thank Jonp - Is there a specific question you have that you would like addressed?

[@jonpig1]

just your thoughts? im always looking for info to improve the process.

[@lesliesweeney368]

Which mix to make this right?

[@michiel7206]

Anything planned on bioconcrete and the self-healing capabilities of it? :)

[@TylerLey]

Michiel - I don't have a lot of experience with that. I know some things about it but I am not sure we know how reliable it will be over time.

[@mirokefurt4740]

Is "lava Rock" a good aggregate ? It is light and porous.

[@TylerLey]

Pumice can be a good aggregate depending on what you are trying to do. I would worry that it would cause ASR because of the chemical makeup but I don't know anyone that has studied it. The voids inside of it might be able to absorb some of the gel.

[@mirokefurt4740]

@@TylerLey Thanks !!!

[@akoponen]

Rather than use fossil fuels to make cement, using focused solar energy will provide the heat while not contaminating the cement with combustion by products. In the long run it should be much less expensive and better for the planet as well.

[@gervaissawyer4779]

Have you given up on concrete videos? Do you know anybody who would like a nice Los Angeles aggregate testing machine? Located London UK. Good commision offered.

[@kiranrampp19]

Sir, How can we distinguish crack pattern of ASR from other cracks??

[@TylerLey]

Good question. Unfortunately, it takes a long answer. ASR cracking will depend on the structure, the amount of stress, and the reinforcing layout. It will make any structural cracking larger because that is typically where the most tension is. If there is a lot of restraint then it will go in the opposite direction. If there are low stress or not much restraint then the cracks will map like cracks. I thought about making a video over this but I was afraid most people wouldn't be interested.

[@kiranrampp19]

@@TylerLey Thank you sir. Actually, we need to know the cause of each type of cracks. Moreover, if we know the cause by visual observation, then we can easily fix it. So, if you can, please make a video regarding this. You can explain other crack patterns also. It will help us a lot.

[@TylerLey]

@@kiranrampp19 It is not a good idea to just diagnose a concrete problem based on a visual observation of the cracks. It is easy to be fooled. You should verify this with other measurement methods. I don't think this is a good thing to put in a video.

[@kiranrampp19]

@@TylerLey Actually, crack patterns are different for different durability issues. For example, cracks aligned parellel to rebar in most cases of corrosion. After that, we need to do more in-depth methods to confirm these issues. But, if we have general idea about the crack patterns, It will be easy for choose durability tests. Especially, in field we can not do all type diagnose test for durability problems.

[@kiranrampp19]

I am just saying Sir and I wanted to share my experience too. I faced these issues in the field several times.

[@MissJami]

High pH is an indicator of alkalinity. Low pH is acidity. Under acidic conditions, the solution is red, and under alkaline conditions, the solution is blue... what gives?

[@rhinohog75]

Check the video at 3:45. Looks right to me - red in alkaline conditions.

[@TylerLey]

Thanks again Jami! I think the video is correct. pink or red = high pH The dark items in the picture are aggregates. The light rims around the aggregates are cement paste that was NOT stained by the pH indicator. This means these areas have a lower pH. This is caused by a local attack of the cement paste by the aggregates. This attack is caused by the alkalis in the cement paste attacking the aggregates in the system. I see how this can be confusing. The HIGH pH attacks the aggregates and makes the cement paste have a LOW pH. I could do another video on ACR to try and make this more clear. Thanks so much for the question! It helps me rethink my explanations!

[@TylerLey]

Thanks Rhino for stepping in and helping!

[@Wild_Bill57]

What's the best aggregate?

[@TylerLey]

The one that is affordable and able to give you the properties that you want. =) For ASR I would try to use limestones that are locally available. It depends though because some deposits can have chert that are reactive. The best is to look at long term field performance.

[@lethaldriver]

considering this, it seems like most of the concrete is doomed. like they are diagnosed to have "cancer" in a period of 10 years

[@MissJami]

All concrete cracks. You mean yours doesn't??

[@TylerLey]

Jami - Thanks for the question. You are right that concrete does sometimes crack. These cracks usually form in the first three to six months or after the first winter. With ASR the cracks just suddenly appear after 8 to 10 years. The cracks may form in totally new places than the old cracks and they slowly get worse. With ACR the cracks form after about 1 year and they get HUGE fast.

[@PeterFournierSamalander]

I’ve been Rome and seen 2,000 year old concrete that is not cracked. Why not?

[@thinkpadBentnoseTheBlind]

@guss whu I have seen pea stone round stone used that lasts much longer than a jagged edged crushed stone in many applications. Methinks they had other secrets.

[@MitzvosGolem1]

Peter Fournier Soft lime concrete low psi.

[@jr3474]

romans did not use fast food engineering as nowdays. "Insert the flaw by design so it does not last" is the norm of today

[@ramcid007]

Hi ,,,, bro i am working in cementaid asia pvt ltd ..please explained about the water proofing chemical ....(our company using ammonia based chemicals...)i dont know what it is because i am new .....pls give me ur whasapp no ...i will send u details .... after u explain me ...thank u..broooo....

[@julikb]

another idiotic thumbnail