tqsm for the knowledge! I am a civil eng. students,currently in 3rd year from Malaysia,im taking this Advanced Concrete and Material elective courses.and today is my final exam for this subject.Im really have confusion in this ASR.but after watching this..I got the new info bout how to overcome ASR .tq..
Thank you Tyler - Question for you - I have some exterior decorative concrete (various colored topical glass) where ASR is going to require me to replace panels, but others that have not reacted much yet. Is there a sealer (Silane?) I can use on the existing panels to prevent ASR on these existing panels not yet reacting?
Thank you very much for sharing your knowledge, great video. I will add that micro reinforcement with microfibers also inhibits cracking formation but increase cost.
Looks like no one comments? I work in coatings and silanes are good but an acrylic sealer can be good - I especially like my competitors (euco) solvent based acrylic sealer. The silanes don’t work quite like your photos show, someone cherry picked those images I think, but you chemical description is pretty good, they are essentially reactive waxes that do not form a film, so if you have a vapor drive outward they let the concrete loose moisture better than any film (s.a. acrylic). They are not as good for wind driven rain as a sealer, so sometimes the sealer wins. I’ve see silanes last about 5-10 years and sealer generally only 2-3. Generally a sealer is used when you want to color the concrete. Silanes can exacerbate iron stains, so often silane is a looks don’t matter thing. Back in the day when we could use solvent we’d silane then seal with a solvent borne sealer, most of the time you cant use a WB sealer over silane treated concrete, and since it last over 5 years you have to decide what look you want before you pick a coating. Last, if you have humor, to an engineer the concretes surface is not a big deal as long as the rebar is safe. To me in coatings its the outer 10 mils I live and die by. Concrete tests do not capture this. Most clients will also judge every book buy its cover - so the surface cracks are bas for business. I think some aggregates scavenge alkali like fly ash does, just from observation of surface efflorescence - but not sure.
There was a concrete company in Stafford Springs CT named JJ Mottes. Turns out they used an aggregate in their concrete that contained an iron sulfide mineral pyrrhotite from Beckers Quarry. Now 30 years later thousands of foundations, etc. are crumbling. Some homeowners are having their foundation replaced at great expense. Its lowering home values and sales in the area. I don't know if thats ASR, but it's pretty devastating. Are you aware of this and can you think of any remedies. Two ideas I have heard were surface bonding cement or a spray on polyurea coating like Line-X.
Thanks! This is called iron pyrrhotite attack. I don't know of a good solution once the concrete has been cast. The aggregates are dissolving in the concrete and then expanding.
So what do you do wh3n the asr has already started to corrode the steel and there is pitting in the rebar Doors that warrant stripping iam currently doing a 1000m2 podium like 5his at the moment Love your channel thanks for the great info and vids
I should make a video about this. You are the second person to ask about this topic. When fly ash, slag, etc. react in concrete they form this glue like material that holds concrete together. The composition of this glue is dependant on what is swimming around when it forms. This means the glue will grab stuff that is swimming around and make it part of the glue. Kinda like wet glue!!!! If there are alkalis present then they will become part of the hydration product. This removes some of the alkalis from the solution and the alkalis won't be able to react with the rock to form ASR gel. Let me know what you think.
"Pretty Good" is not acceptable by anyone paying for a concrete job... looks bad... is bad... because it leads to other problems... Thanks for the video!
I worked at a water treatment plant for many years.Concrete that was poured in the 40s using granite was still in use today where silica Quartz aggregate that was poured in the 80s.Has already self destructed because of ASR
Wouldn't it cause other problems if the pH of the concrete is reduced due to reactions of SCMs with CH? Like decrease the passivation of your rebars and then allow corrosion to happen?
Thanks for the question! You bring up a good point and one that people in the concrete world don't like to talk about. Sometimes we design for one thing and it causes problem in another area. If you have reactive aggregate and you want to design for a long lasting structure then you need to design for ASR at the expense of performance in corrosion and carbonation. If you are worried about all of these then you could modify other things to design for corrosion and carbonation like increasing your cover, including a corrosion inhibitor, or possibly using a different type of steel than conventional rebar. The use of SCMs will also decrease your permeability and so that will also help with corrosion and carbonation.
@@TylerLey Thanks for the quick answer! I have an exam in concrete technology on monday, and your videos have helped me out quite a bit at getting additional information on topics like AAR!
First investigate your source by sending samples to Geology department they will suggest about ASR and also provides u remedies regarding this cancer .
This video is very informative for the research that I am working on now, thank you.
Finally a video worth watching.
Good explanation on ASR. Thanks.......Good job.
tqsm for the knowledge! I am a civil eng. students,currently in 3rd year from Malaysia,im taking this Advanced Concrete and Material elective courses.and today is my final exam for this subject.Im really have confusion in this ASR.but after watching this..I got the new info bout how to overcome ASR .tq..
Lisa,
I am glad this helped. I hope your exam went well and you found a few of my other videos on ASR. Thanks!!!!
Really nice video! It gave some really important information on ASR treatment! Thanks!
Thank you Tyler - Question for you - I have some exterior decorative concrete (various colored topical glass) where ASR is going to require me to replace panels, but others that have not reacted much yet. Is there a sealer (Silane?) I can use on the existing panels to prevent ASR on these existing panels not yet reacting?
Thanks dude!
Love your work!
Thank you!!!
Thanks tyler.., you explaination very good
I'd like to hear your opinion of the brand new repaired Oroville Dam main spillway. How did they do?
Thank you very much for sharing your knowledge, great video. I will add that micro reinforcement with microfibers also inhibits cracking formation but increase cost.
Very true! Check this video out.
th-cam.com/video/jWFncYgbCCg/w-d-xo.html
Microfibers acts another Way to protect against cracks.....its ASR cracking
U have to stop this cancer otherwise fibers cannot work for it.
Great video. What are your thoughts on utilizing Carbonate micro-fines (ASTM C1797) to help mitigate potential ASR?
Looks like no one comments? I work in coatings and silanes are good but an acrylic sealer can be good - I especially like my competitors (euco) solvent based acrylic sealer. The silanes don’t work quite like your photos show, someone cherry picked those images I think, but you chemical description is pretty good, they are essentially reactive waxes that do not form a film, so if you have a vapor drive outward they let the concrete loose moisture better than any film (s.a. acrylic). They are not as good for wind driven rain as a sealer, so sometimes the sealer wins. I’ve see silanes last about 5-10 years and sealer generally only 2-3. Generally a sealer is used when you want to color the concrete. Silanes can exacerbate iron stains, so often silane is a looks don’t matter thing. Back in the day when we could use solvent we’d silane then seal with a solvent borne sealer, most of the time you cant use a WB sealer over silane treated concrete, and since it last over 5 years you have to decide what look you want before you pick a coating.
Last, if you have humor, to an engineer the concretes surface is not a big deal as long as the rebar is safe. To me in coatings its the outer 10 mils I live and die by. Concrete tests do not capture this. Most clients will also judge every book buy its cover - so the surface cracks are bas for business.
I think some aggregates scavenge alkali like fly ash does, just from observation of surface efflorescence - but not sure.
Great video, dr Tyler !!!
Thanks!!!
In addition we are using ASTM C295 ; petrography test to analyse the ASR and ACR..
well done!
Nice work
In your video you talked about membrane...any reference of Astm about it.
There was a concrete company in Stafford Springs CT named JJ Mottes. Turns out they used an aggregate in their concrete that contained an iron sulfide mineral pyrrhotite from Beckers Quarry. Now 30 years later thousands of foundations, etc. are crumbling. Some homeowners are having their foundation replaced at great expense. Its lowering home values and sales in the area. I don't know if thats ASR, but it's pretty devastating. Are you aware of this and can you think of any remedies. Two ideas I have heard were surface bonding cement or a spray on polyurea coating like Line-X.
Thanks!
This is called iron pyrrhotite attack. I don't know of a good solution once the concrete has been cast. The aggregates are dissolving in the concrete and then expanding.
Very excellent...
So what do you do wh3n the asr has already started to corrode the steel and there is pitting in the rebar
Doors that warrant stripping iam currently doing a 1000m2 podium like 5his at the moment
Love your channel thanks for the great info and vids
Hi Tyler you mentioned it cracks if it has a high PH, what is an acceptable PH? Can it be used in small dams?
What sealer would be a good choice for outdoor concrete?
I’m going to build my house with icf
How do I properly hydrate concrete that is wrapped in foam?
The god is back!
Thanks Orion! Another one coming tomorrow.
great vid
Thanks Tyler! Can you elaborate a little on what you mean when you say "SCM's can bind alkalis in their hydration product"?
I should make a video about this. You are the second person to ask about this topic.
When fly ash, slag, etc. react in concrete they form this glue like material that holds concrete together. The composition of this glue is dependant on what is swimming around when it forms. This means the glue will grab stuff that is swimming around and make it part of the glue. Kinda like wet glue!!!!
If there are alkalis present then they will become part of the hydration product. This removes some of the alkalis from the solution and the alkalis won't be able to react with the rock to form ASR gel. Let me know what you think.
This must be why they are going around to all the bridge in Ontario and expanding the bases
do u know bypass dust in cement plant s ? it is full of alklai , can we use it for UHPC where there is no aggregate
i am arch engineer ,penn state
Great thanks to you sir
What do you think about adding lithium to the mix design?
Lithium silicate?
Thanks Sir
Is rich-silica materials sensitive to ASR?
It depends on the form of the silica and when it reacts.
"Pretty Good" is not acceptable by anyone paying for a concrete job... looks bad... is bad... because it leads to other problems... Thanks for the video!
Glad you enjoyed it!
Does basalt or granite prone to ASR ?
I worked at a water treatment plant for many years.Concrete that was poured in the 40s using granite was still in use today where silica Quartz aggregate that was poured in the 80s.Has already self destructed because of ASR
Great
Thanks!
Wouldn't it cause other problems if the pH of the concrete is reduced due to reactions of SCMs with CH? Like decrease the passivation of your rebars and then allow corrosion to happen?
Thanks for the question!
You bring up a good point and one that people in the concrete world don't like to talk about. Sometimes we design for one thing and it causes problem in another area. If you have reactive aggregate and you want to design for a long lasting structure then you need to design for ASR at the expense of performance in corrosion and carbonation. If you are worried about all of these then you could modify other things to design for corrosion and carbonation like increasing your cover, including a corrosion inhibitor, or possibly using a different type of steel than conventional rebar. The use of SCMs will also decrease your permeability and so that will also help with corrosion and carbonation.
@@TylerLey Thanks for the quick answer! I have an exam in concrete technology on monday, and your videos have helped me out quite a bit at getting additional information on topics like AAR!
Great! Let me know how it goes.
First investigate your source by sending samples to Geology department they will suggest about ASR and also provides u remedies regarding this cancer .
Why can't you place your camera a little bit higher? Its no fun looking up inside of your nose.
🤣 the little things that irk little men