Love me some fly ash. There was a shortage of lime in my area. I made a deal with our local coal fired cement plant to bag up semi loads of fly ash. 25 years later, the local brick layers and traditional stucco people are still using it. A major benefit for finishes is it does not require a primer coat before paint. Thanks for bringing this up.
I contracted your enthusiasm, Professor. Good, great video. I am so in! Your video explains one of the reasons why I am planning a graduate study on Sustainable and Resilient Structural Engineering, Mechanics and Materials (SR-SEMM).
Great video Professor. This one makes me think of a solution every concrete producer can employ. Why not use Grey Water. All day long, we as concrete producers make Grey Water. Every time we wash down or wash out we create something that can help us. All of our returned concrete can be washed out producing large quantities of Grey Water. Grey Water if handled correctly adds great value to concrete, while lowering water, cement, and SCM costs. Recycling water with suspended fines cleans also offers a source of recycled aggregates.
I think that is a great question. The key would be to find an easy way to determine how the water may change your concrete. I think it can be done! It just takes a little effort. Gray water can have a big impact on the performance of admixtures, setting, and strength gain. A lot of people avoid it because they have enough trouble as it is providing high quality concrete. I do think this is very doable.
@@TylerLey Hi Professor. Grey water use requires some spending on equipment to hold and keep the fines suspended. Not expensive. You also need someone to watch it and accumulate the data - that will change with the seasons. Strength gain, workability, finish ability, and advanced setting times are all within reach with grey water. Many more advantages to list. Great videos - keep them coming.
You are so good at what you are doing, I wish I were young enough to go back to school and study directly under you. I can't stop watching your videos. They give us tools to make better decisions. Thank you.
A nearby batch plant keeps test cylinders for many years. They tell me that the fly ash component keeps increasing in strength 7 years later. Good to know plenty is still out there, thanks!
Fly ash is such a public health safety issue when stored in heaps and left uncovered, that it is incredible how more of it is not used. In Puerto Rico we have one coal powered power plant, and it produces off-spec fly ash. Studies (funded by the power plant, but well intentioned) have shown their ash additive to be more than adequate for use in commercial concrete, but the codes will not permit it. It is a missed oportunity of not only using it in concrete, but of solving the ash storage problem. Great video, and I hope we can get some of the standards agencies on this.
Yeah but it also leaks toxins into the air poisoning people and animals. It is not less toxic when you put into into a cement. You are just changing the place the toxic material stored. No disagreement that Fly Ash performs very well for making a strong cement structure, but we should not use toxic materials in our concrete. There is a building in Hong Kong where they used Fly Ash in the cement and they turn the air conditioning off on the weekends because people are not working in the building. People have gone in on the weekends and the toxic off gassing fumes from the fly ash have sent them to the hospital. No one is disagreeing that Fly Ash is toxic yet no one is doing the testing to see the affects on people, animals, etc and it has become an actual standard now which is just crazy. I am curious about slag though.
Off spec as in particle sizes are too large? Problem is a lot of the ponded ash is reject fly ash or bottom ash, with particle sizes above 40 microns. I’ve seen a few studies on the use of r-FA and bottom ash as river sand replacement. That would help reduce size of ash ponds but doesn’t help as much for SCM replacement as stored fly ash and bottom tends to be far less active as a binder. GGBS seems to be the goto replacement for fly ash as an SCM. Check out papers on typeset.
We have solved the issue ! , We are BSc students in university of engineering and technology, lahore We were able to replace 50% of fly ash with another material and develop a green concrete !
I've heard that part of the problem is new clean air act regulations have resulted in high amounts of carbon in the fly ash so a lot of the ash produced just isn't usable in concrete.
I live in northern New Mexico and the fly ash concrete produced by one company does not stand up to the winters here like the portland based concrete produced by another company. The fly ash starts falling apart the first winter.
What would it take to generate a body of the necessary research to establish what slashcharacteristics are truly necessary to meet specifications? You are right that people need knowledge to have the confidence to use his materials. But, it’s easier to change the regulations to conform with actual requirements if we’ve established what the actual requirements are. Stupid to be operating with out of date info. I’d love to see states supporting the sampling and harvesting of these/ponds, centralizing them into material stock piles closer to appropriate transportation, like railways. That way, when/is needed, they would be a resource easier to talk. Flashponds are a situation in which something valuable has been miscategorised. Like a library book stored on the wrong shelf. Get those books off the shelves, check their decimal numbers, and put them in the appropriate place so that those who need them can get them easily. As call flashdwindles, the value of these “ found” Services will prove a sound investment. Besides, some times the return is in a more viable future, rather than in cash money for an individual. That is the failing of 100% capitalist thinking: things which benefit everyone often don’t get done because they are not sufficiently profitable to one person. But, the state might see the profitability and have the resources to make what is necessary happen in order to profit users of cement, and therefore it’s citizens.
Dr. Ley, are you working on projects to determine those "nutrition facts" for the fly ash? It seems like if you want to increase the confidence that the "new fly ash" will work, then it will need a lot of research done to back it up. I look forward to seeing more videos about innovation and advancements in the field!
China produces around 600 million tons of fly ash each year and uses about 70%... so around 180 million tons are landfilled in China each year. Current estimates of landfilled/stored/ponded ash in China are around 2 - 2.5 billion tons. India produces around 200 million tons per year and and their utilisation rate has increased substantially over the last 15 years to around 70-75%. Estimates of landfilled ash in India are perhaps 1 billion tons... However, not all of if it stored in landfills where recovery is viable. Those are the two largest largest producer nations globally. www.asiancoalash.org
Long distance transportation of construction materials is an economic issue. When it can't be avoided one will even import sand, but it's not your first choice.
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?
Man, this is a part of the change in fuels we need to talk about. BTW, I've worked in coal, nuclear, biomass and petrochemical plants since the 70's. Can I get a thumbs up for electrostatic precipitators?
I like your videos because they are related to civil engineering, I am a future civil engineer. And thank you professor for giving such great knowledge. The are really helpful. Latest watched video was your alkali agg reaction.
We made our geo polymers concrete Our polymers are fly ash & silica fume, which percentage are best between these two materials according to research ???
I would contact local ready mix suppliers to see what they are using. When you choose a fly ash you need to think about what you want it to be able to do or resist. Just like when you go to the store and buy peanut butter. Do you want it for a sandwich, or a cookie, or something else. This will change whether you buy organic, creamy, chunky, etc. For my ferrocement I think any fly ash that is commonly used locally in concrete would be a good choice.
I have long wondered why cement manufacturers don't use setups to focus solar rays for providing much of the heating required in the manufacture. Seems that in many places this would save them money in the long run, giving them a competitive advantage as well as being better for the planet.
Thanks for the question. Do you mean how does the mixture design change with different types of aggregates or do you mean how the performance of the concrete changes?
@@TylerLey i seen a video where someone explain that 100 percent synt oil is better because oil particles are same size thus they react better under heat and pressure ......that kind of explanation will do it if too wide the question ..thanks
Why did the hard rock hotel collapse? Also have you ever watched the “Construction & Engineering failure Analysis” TH-cam channel? He is an engineer explaining why the hotel failed, but I still want to hear your opinion
Douglas - Aircrete video is coming. I bet I can get it out before the end of the year. We have some really cool results so far. I think people will really like it.
Thanks Allan, It depends on what is off about the fly ash . Sometimes the specs were just written a certain way because that is what has always worked and they are not based on actual performance. If you had a spec that was performance based then we could get away from some of this we have always done it this way mentality. Please don't think I am for throwing out all existing specs. I think they are often very good but I do think they can be improved. Sometimes the fly ash is so bad that they should not be used in concrete. We should give people ways to determine this and let the market decide what they want to do about it.
The main place I order my concrete from is switching one of the batch plants from flyash to slag☹ I have become a believer that fly ash is stroger than slag the other company uses it and it cracks more more map cracks also
your informative videos are awesome. I’m sure I’m stating the obvious but can’t we repurpose the coal burners and design them to primarily produce fly ash instead of only as a ‘byproduct’🤷♀️ If it’s efficient enough then it might not produce too much bad pollution🤷♀️ Maybe I could produce flyash and help heat my house at the time 🤷♀️
I use ash in my Mortar mix . Not Fly ash , but any ash Oak , Pine , Maple , etc . I have made mortar/stone fire places at national camp sites that the rangers are amazed that they lasted over 10 yrs. [can't fight vandals] . I have tried a bit of ash in my concrete mixes and WOW. Spam brought to you by You Tube.
here's an example in my country where I live had a coal power plant which produces a large amount of ash this ash is used in a concrete production plant in my country macedonia and albania but the problem is those green environmentalists who are trying to switch over to the gas station and if they do that there will be no more cheap cement in the Republic of Macedonia because in my country 50kg of cement costs 5.5 $ аmerican dolars
Thanks Goce for the story. I know that things will be different but I think there will be new solutions to this problem. It will not be easy but I think it can be solved without such high prices.
Fly ash is still massively used in China as there are still tons of power plants that burn coal. It is about 20 us dollars/ton and is rated roughly based on its degree of fineness
Hello! I want to start a concrete and cement import business in Africa. I am wondering if I could use local agriculture waste as a substitute for fly ash. Is that realistic?
Excellent! Very good presentation. Natural speaker/teacher. Here at Burgess Pigment Company we produce a metakaolin…OPTIPOZZ. An excellent Pozzolan. If you need a metakaolin/pozzolan for any of your projects let me know. We would be happy to help.
Pro tip.. Raise your tripod / camera height by a few inches so we aren't looking up your nostrils so often 🤣🤣 Also I've got a few questions about carbon nano technology - - have you noticed it affects air content when combined with other additives???
Is this one-third in concrete or one-third period? Other sources indicate more than 60% fly ash reuse, which I'm sure included as a structural filler for infrastructure... and golf-courses; yuck!
We miss you. Love the videos. Just one small idea. I know it is minor and cosmetic, but your face in the video is badly over-exposed all of the time. That is ugly. You are not. The photography is.
I use ash in my Mortar mix . Not Fly ash , but any ash Oak , Pine , Maple , etc . I have made mortar/stone fire places at national camp sites that the rangers are amazed that they lasted over 10 yrs. [can't fight vandals] . I have tried a bit of ash in my concrete mixes and WOW. Spam brought to you by You Tube.
![[Re:all TREASURE] EP.6 in 방콕ㅣ🚩 쩡캠의 방콕 투어 빵 마이 와이 👍](http://i.ytimg.com/vi/uyFw-nItA_s/mqdefault.jpg)
Love me some fly ash. There was a shortage of lime in my area. I made a deal with our local coal fired cement plant to bag up semi loads of fly ash. 25 years later, the local brick layers and traditional stucco people are still using it. A major benefit for finishes is it does not require a primer coat before paint. Thanks for bringing this up.
Thanks for the awesome story!!!
1:14 Coal Powered Plants are not going away
I contracted your enthusiasm, Professor. Good, great video. I am so in! Your video explains one of the reasons why I am planning a graduate study on Sustainable and Resilient Structural Engineering, Mechanics and Materials (SR-SEMM).
Great video Professor. This one makes me think of a solution every concrete producer can employ. Why not use Grey Water. All day long, we as concrete producers make Grey Water. Every time we wash down or wash out we create something that can help us. All of our returned concrete can be washed out producing large quantities of Grey Water. Grey Water if handled correctly adds great value to concrete, while lowering water, cement, and SCM costs. Recycling water with suspended fines cleans also offers a source of recycled aggregates.
I think that is a great question. The key would be to find an easy way to determine how the water may change your concrete. I think it can be done! It just takes a little effort. Gray water can have a big impact on the performance of admixtures, setting, and strength gain. A lot of people avoid it because they have enough trouble as it is providing high quality concrete. I do think this is very doable.
@@TylerLey Hi Professor. Grey water use requires some spending on equipment to hold and keep the fines suspended. Not expensive. You also need someone to watch it and accumulate the data - that will change with the seasons. Strength gain, workability, finish ability, and advanced setting times are all within reach with grey water. Many more advantages to list. Great videos - keep them coming.
Another great video. I'm just a concrete mixer driver and sometimes batch plant operator(since 2003). I like the info I get from your videos.
Hey I am fly ash supplier from India and it was so cool to hear this from you
You are so good at what you are doing, I wish I were young enough to go back to school and study directly under you. I can't stop watching your videos. They give us tools to make better decisions. Thank you.
A nearby batch plant keeps test cylinders for many years. They tell me that the fly ash component keeps increasing in strength 7 years later. Good to know plenty is still out there, thanks!
Thanks for the comment!! That is a such a cool story. It is rare to have data from samples that old.
Fly ash is such a public health safety issue when stored in heaps and left uncovered, that it is incredible how more of it is not used. In Puerto Rico we have one coal powered power plant, and it produces off-spec fly ash. Studies (funded by the power plant, but well intentioned) have shown their ash additive to be more than adequate for use in commercial concrete, but the codes will not permit it. It is a missed oportunity of not only using it in concrete, but of solving the ash storage problem. Great video, and I hope we can get some of the standards agencies on this.
Yeah but it also leaks toxins into the air poisoning people and animals. It is not less toxic when you put into into a cement. You are just changing the place the toxic material stored. No disagreement that Fly Ash performs very well for making a strong cement structure, but we should not use toxic materials in our concrete. There is a building in Hong Kong where they used Fly Ash in the cement and they turn the air conditioning off on the weekends because people are not working in the building. People have gone in on the weekends and the toxic off gassing fumes from the fly ash have sent them to the hospital. No one is disagreeing that Fly Ash is toxic yet no one is doing the testing to see the affects on people, animals, etc and it has become an actual standard now which is just crazy. I am curious about slag though.
Off spec as in particle sizes are too large?
Problem is a lot of the ponded ash is reject fly ash or bottom ash, with particle sizes above 40 microns.
I’ve seen a few studies on the use of r-FA and bottom ash as river sand replacement. That would help reduce size of ash ponds but doesn’t help as much for SCM replacement as stored fly ash and bottom tends to be far less active as a binder. GGBS seems to be the goto replacement for fly ash as an SCM. Check out papers on typeset.
The F.A. has been proven to be an excellent durability enforcer. We've done a lot of ASTM C 1202 based tests and the results are amazing.
I agree. Thanks for sharing.
We have solved the issue ! ,
We are BSc students in university of engineering and technology, lahore
We were able to replace 50% of fly ash with another material and develop a green concrete !
I've heard that part of the problem is new clean air act regulations have resulted in high amounts of carbon in the fly ash so a lot of the ash produced just isn't usable in concrete.
We’ll might use up the 170yr reserves & then some building 7m concrete sea level rise walls around the coast
I live in northern New Mexico and the fly ash concrete produced by one company does not stand up to the winters here like the portland based concrete produced by another company. The fly ash starts falling apart the first winter.
What would it take to generate a body of the necessary research to establish what slashcharacteristics are truly necessary to meet specifications? You are right that people need knowledge to have the confidence to use his materials. But, it’s easier to change the regulations to conform with actual requirements if we’ve established what the actual requirements are. Stupid to be operating with out of date info.
I’d love to see states supporting the sampling and harvesting of these/ponds, centralizing them into material stock piles closer to appropriate transportation, like railways. That way, when/is needed, they would be a resource easier to talk. Flashponds are a situation in which something valuable has been miscategorised. Like a library book stored on the wrong shelf. Get those books off the shelves, check their decimal numbers, and put them in the appropriate place so that those who need them can get them easily. As call flashdwindles, the value of these “ found” Services will prove a sound investment. Besides, some times the return is in a more viable future, rather than in cash money for an individual. That is the failing of 100% capitalist thinking: things which benefit everyone often don’t get done because they are not sufficiently profitable to one person. But, the state might see the profitability and have the resources to make what is necessary happen in order to profit users of cement, and therefore it’s citizens.
Dr. Ley, are you working on projects to determine those "nutrition facts" for the fly ash? It seems like if you want to increase the confidence that the "new fly ash" will work, then it will need a lot of research done to back it up. I look forward to seeing more videos about innovation and advancements in the field!
Yes!
Look for more upcoming videos on this topic.
Do you keep up with ACI 318-19? If so, it would be a cool video to talk about updates and changed in concrete design. Not sure if that’s your thing
I think that is a good idea. I teach ACI318-19 this fall in my reinforced concrete design class and so I will see what I can do.
Watch the audio levels on those sound effects. They were a bit loud. Great video though.
I wonder what foreign stores of fly ash are like.
Will do!
I am not sure about foreign storage. I think that is a great question. I bet there is a lot!!!
China produces around 600 million tons of fly ash each year and uses about 70%... so around 180 million tons are landfilled in China each year. Current estimates of landfilled/stored/ponded ash in China are around 2 - 2.5 billion tons.
India produces around 200 million tons per year and and their utilisation rate has increased substantially over the last 15 years to around 70-75%. Estimates of landfilled ash in India are perhaps 1 billion tons... However, not all of if it stored in landfills where recovery is viable.
Those are the two largest largest producer nations globally.
www.asiancoalash.org
Long distance transportation of construction materials is an economic issue. When it can't be avoided one will even import sand, but it's not your first choice.
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?
Man, this is a part of the change in fuels we need to talk about.
BTW, I've worked in coal, nuclear, biomass and petrochemical plants since the 70's.
Can I get a thumbs up for electrostatic precipitators?
Brian - Thanks for sharing. This is definitely a fuel change issue. Electrostatic precipitators are the reason we have fly ash!!!! Yeah !!!!
I like your videos because they are related to civil engineering, I am a future civil engineer. And thank you professor for giving such great knowledge. The are really helpful. Latest watched video was your alkali agg reaction.
Exciting, sign me up.
Would you make a video about aircrete? Is it up to the hype or is it an abomination in the concrete world?
Please upload videos on design of RCC slab and beam
Check this playlist out: th-cam.com/play/PLRq6Z9d0kCT8PCLAQiRXIoXJ14b3RcgUc.html
Please cover nanoclay particles also.
Great topic. We have some work on these but I am still trying to find the best way to present it.
We made our geo polymers concrete
Our polymers are fly ash & silica fume, which percentage are best between these two materials according to research ???
What's the best way the source fly ash in Florida and what specification must it conform to for use in ferrocement?
I would contact local ready mix suppliers to see what they are using. When you choose a fly ash you need to think about what you want it to be able to do or resist. Just like when you go to the store and buy peanut butter. Do you want it for a sandwich, or a cookie, or something else. This will change whether you buy organic, creamy, chunky, etc.
For my ferrocement I think any fly ash that is commonly used locally in concrete would be a good choice.
Thanks very much,@@TylerLey !
1:14 Coal fueled electric power plants are not going away, not soon. What's going to replace them? Not nuclear not solar not wind
I have long wondered why cement manufacturers don't use setups to focus solar rays for providing much of the heating required in the manufacture. Seems that in many places this would save them money in the long run, giving them a competitive advantage as well as being better for the planet.
Hi could you do a video on the specs of concrete depending on the aggregates used or link to it if already made thanks
Thanks for the question. Do you mean how does the mixture design change with different types of aggregates or do you mean how the performance of the concrete changes?
@@TylerLey now that you say itthat way ..both actually and it would be kind if you could explain from a molecular perspective and outward from there
@@TylerLey i seen a video where someone explain that 100 percent synt oil is better because oil particles are same size thus they react better under heat and pressure
......that kind of explanation will do it if too wide the question ..thanks
Why did the hard rock hotel collapse? Also have you ever watched the “Construction & Engineering failure Analysis” TH-cam channel? He is an engineer explaining why the hotel failed, but I still want to hear your opinion
Thanks Larry,
I will probably do a video on this in the future but I am waiting for a few more reports to come out.
More Aircretes with all of the above SCMs... Dr Ley re Aircrete in 2019? Thanks and Giving time of year!
Would like to hear more about foam/aircretes too
Douglas - Aircrete video is coming. I bet I can get it out before the end of the year. We have some really cool results so far. I think people will really like it.
I'd also ask how much effort would it take to make off spec fly ash meet spec?
Thanks Allan,
It depends on what is off about the fly ash . Sometimes the specs were just written a certain way because that is what has always worked and they are not based on actual performance. If you had a spec that was performance based then we could get away from some of this we have always done it this way mentality. Please don't think I am for throwing out all existing specs. I think they are often very good but I do think they can be improved.
Sometimes the fly ash is so bad that they should not be used in concrete. We should give people ways to determine this and let the market decide what they want to do about it.
The main place I order my concrete from is switching one of the batch plants from flyash to slag☹ I have become a believer that fly ash is stroger than slag the other company uses it and it cracks more more map cracks also
What are suitable natural pozzolans that could be used instead of fly ash and slag for the creation of geopolymer?
Is it possible to make floor tiles, marbles with flyash?
How about burn rice husk the alternative useage of fly ash
your informative videos are awesome. I’m sure I’m stating the obvious but can’t we repurpose the coal burners and design them to primarily produce fly ash instead of only as a ‘byproduct’🤷♀️ If it’s efficient enough then it might not produce too much bad pollution🤷♀️ Maybe I could produce flyash and help heat my house at the time 🤷♀️
How about ash from wood, can that be used for concrete?
Good idea. After all, coal used to be wood.
Yes! There is typically not a lot of it available in one place and so people have not used it.
Hate fly ash mixes, always issues when it gets real hot out with the fly ash particles sucking up water and AEA. Less issues with GGBS.
Thanks Alex,
I like slag as well if you can get it locally.
Here a funny question Tyler....can we use the ash collected from fireplaces or barbequeing? Of course....just for home repairs
Good question. I am not sure enough is produced to be that useful but maybe you barbeque a lot. =)
I use ash in my Mortar mix . Not Fly ash , but any ash Oak , Pine , Maple , etc . I have made mortar/stone fire places at national camp sites that the rangers are amazed that they lasted over 10 yrs. [can't fight vandals] . I have tried a bit of ash in my concrete mixes and WOW.
Spam brought to you by You Tube.
here's an example in my country where I live had a coal power plant
which produces a large amount of ash this ash is used in a concrete production plant in my country macedonia and albania but the problem is those green environmentalists who are trying to switch over to the gas station
and if they do that there will be no more cheap cement
in the Republic of Macedonia because in my country 50kg of cement costs 5.5 $ аmerican dolars
Thanks Goce for the story. I know that things will be different but I think there will be new solutions to this problem. It will not be easy but I think it can be solved without such high prices.
احسنت
'Nother great vidy ! Cheers Tyler !
Thanks!
Fly ash is still massively used in China as there are still tons of power plants that burn coal. It is about 20 us dollars/ton and is rated roughly based on its degree of fineness
Thanks for the info! I would like to learn more about how China and other countries are dealing with this.
Hello! I want to start a concrete and cement import business in Africa. I am wondering if I could use local agriculture waste as a substitute for fly ash. Is that realistic?
Cesar NaVillar depends on what the agriculture waste is? If it’s not pozzolanic then probably not
@@liamwalker5194 Burnt rice straw ash. I think that's what he meant
I'm in! I love your videos.
Awesome!!! Let's do this!!!
Thank you sir 👌
Thanks!
Coal is awsm
Subscribed! We need more PhDs to do TH-cam videos.
Previous reference = Peter Kirby.
Excellent! Very good presentation. Natural speaker/teacher.
Here at Burgess Pigment Company we produce a metakaolin…OPTIPOZZ. An excellent Pozzolan.
If you need a metakaolin/pozzolan for any of your projects let me know. We would be happy to help.
Pro tip.. Raise your tripod / camera height by a few inches so we aren't looking up your nostrils so often 🤣🤣
Also I've got a few questions about carbon nano technology - - have you noticed it affects air content when combined with other additives???
Every time I watch your videos I come away thinking money.
I think that is good =).
Are you this hysterical in your lectures too?
Is this one-third in concrete or one-third period? Other sources indicate more than 60% fly ash reuse, which I'm sure included as a structural filler for infrastructure... and golf-courses; yuck!
There are gigatons of flyash that will last for many decades, possibly a century
So we need energy to make opc, why not continue with coal power plants. Win win
Coal plants are more emissions and more expensive than natural gas. Energy production is the focus and the ash is secondary.
We miss you. Love the videos. Just one small idea. I know it is minor and cosmetic, but your face in the video is badly over-exposed all of the time. That is ugly. You are not. The photography is.
Yet another reason to despise the modern environmental movement.
I use ash in my Mortar mix . Not Fly ash , but any ash Oak , Pine , Maple , etc . I have made mortar/stone fire places at national camp sites that the rangers are amazed that they lasted over 10 yrs. [can't fight vandals] . I have tried a bit of ash in my concrete mixes and WOW.
Spam brought to you by You Tube.
Previous reference = Peter Kirby.