Alternative Cements (ACMs) | Intro, Facts, and Uses
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- čas přidán 2. 07. 2018
- This video explains alternative cements or alternative cement materials (ACMs). The video specifically discusses calcium aluminate (CAC), calcium sulfoaluminate (CSA), and alkali activated (AA) or geopolymer cements and compares them to portland cement. A classification procedure of ACMs is given along with important facts, environmental impact, strength gain, and an overview of their durability.
The benefits and challenges with each alternative cement is discussed and recommendations are given about what environments the cements can be used when durability is a concern.
This research was sponsored by the FHWA under the Exploratory Advanced Research program. The project was led by Georgia Tech, in collaboration with Oklahoma State University, Tourney Consulting, and the US Army Corps of Engineers.
Some details about the work can be found here: www.fhwa.dot.gov/advancedrese...
My website is: www.tylerley.com
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Great video. I'm sure its on your TODO list and in planning process and look forward to your video on aerated concrete or whatever name preferred, especially about the DIY innovators who are making mixes for sheds and domes etc.
Douglas - It is on the list. Thanks again for all the links you sent.
hello again dr . yes , i want a CSA additive. It is designed to be, and MUST be, blended with portland cement and actually speed up strength gain and use in concrete countertop.
Wow you make cements exciting again!
Awesome video! Thank you! :-)
I look forward to hearing more about the AA cements. How much variance is there in the different types (are there any with good blocking of ion-penetration?).
Super informative! Can you do a video addressing polymer concretes and the advantages/ disadvantages they provide?
Highly informative sir..!!
Thanks! I will probably make more on this topic soon.
Very interesting topic.
Thanks Ali!
Great job dude!!
Thanks!
Thanks for the awesome content. Some folks might quibble with equating AAMs with Geopolymers, however. Like OCP, AAMs create monomer hydration products-they aren’t polymers at all. Geopolymers are polycondensates. Totally different chemistry. At least that’s my understanding. I could easily be wrong.
Great research stuff. My research area is on cementitious materials using recycled plastic Waste.
i love your videos
can you pleeease make a video on quicklime and gypsum?
Please talk about Ferro cement boats and how to repair and paint.
Thanks
Bill
Isn't it standard for OPC to be blended with CSA or CAC and gypsum in SLCs (self levelling compounds) for a couple of decades now? In most recipes where walk on time and ease of flow is prioritised, compressive strength (28d) is usually 30 or 35 MPa though.
Apologies for being so ignorant, but I did not see you include slacked lime, or are you counting the opc for basically clinkered\slacked lime? Not trying to sound snotty but having a problem finding a clear, simple statement of opc. Guessing a little\lot here, but slacked lime, gypsum and clinkered ash?
If you would be so kind to point me to video that covers the basic opc, I would be very appreciative. Thanks, great vids, 😝 not always sure what I’m covering but learning a lot, thanks. 🙏
Love your videos Tyler. Can you tell me more about the cons of CSA and maybe also compare this to opc + 2% calcium chloride for durability and reaction with steel work.
Brad - Thanks for the compliment and message!
CSA has some problems with salt scaling and freeze-thaw performance. You can solve this by using a low w/cm and adding a polymer to the mixture. The material can also allow outside chemicals into the concrete. The polymer helps with this. Long term reactions of the CSA may make this better. We are studying this right now. OPC + CaCl will gain strength quickly but it can put any steel that you have inside of it. If you are not concerned about corrosion then the OPC + CaCl can be a good choice for rapid strength gain. Unfortunately, most concrete contains some type of reinforcing steel and so CaCl has been banned in those cases.
Tyler Ley thanks for the reply Tyler. I am setting up some volumetrics using CSA for steel reinforced pavement slabs. Do you have any videos on flexural strength testing?
Yes! I do. Check this video out: czcams.com/video/HB09SPIX7Iw/video.html I have a playlist of other videos that may be helpful: czcams.com/play/PLRq6Z9d0kCT8PCLAQiRXIoXJ14b3RcgUc.html
Sir, ACM's manufactured from only flyash have a problem of high porosity,but I have made geopolymers from a blend of flyash and slag and there porosity is much lower.Though I must add that I subjected them to thermal curing .The residual compressive strength of the blended composite after sulphate exposure was also quite high .Though it didn't do that well when exposed to elevated temperature when percentage of slag was high.
Thanks Kushal - I agree that the properties of geopolymers depend heavily on what powder and liquid you use. There is a lot of work to do in this area. Most people feel that a geopolymer that you have to heat is not practical. I tried to let people know these results were only for the materials that we used in our study. Please keep going and let us know what you find! Thanks for the comment.
Sir,I am also working on water cured blended geopolymer composite,the results regarding mechanical properties are good,but durability properties especially behaviour against acid and elevated temperature are not that good.We are trying by adding various nano materials graphene oixide to improve it's properties.By the way sir, you are one of the best things to happen to the world of concrete since admixtures😁
Thank you, Kushal! All the best on your research.
Dr Ley,if I can help you in any way regarding content creation for your channel,please let me know.I really want to be associated with your channel.
What about comparison cost ? And where do you buy those ACM ?
Alejandro - The cost for ACMs are more than OPC. Depending on the mix they can be two to three times the cost of portland cement. This won't make the cost of the mix increase by two or three times since the cement content is only part of the volume. There are a lot of companies that sell bagged products that contain ACMs. They are typically marketed as rapid setting cement or concrete.
hi dr ley . about CSA cement > if we do not have access to this kind of cement , is there an alternative to this?can use CAC+gypsum and what percentage?
What properties are you trying to achieve? Do you want rapid strength gain?
@@TylerLey hello again dr . yes , i want a CSA additive. It is designed to be, and MUST be, blended with portland cement and actually speed up strength gain and use in concrete countertop.
How about the natural cements that were used prior to the invention of Portland cement? Some have lasted thousands of years, since the Roman period.
Those cements were made from lime and volcanic ash
It seems like ACMs may very well provide solutions to 3D printing homes soon. I sure would like to build a machine that contractors would buy to accomplish 3D home printing with ACMs. Now that would help move and shake the economy. It would also improve entry level home ownership by driving down values. Why by and expensive old deteriorating wooden home when you could by a brand new concrete printed home that will barely deteriorate any over several lifetimes? Anyone want to get in on this?
If fly-ash and slag requires a lot of heat, how can it be "non-clinkered"?
You are right, but since the fly ash and slag are byproducts the carbon accounting doesn't assign the energy intensity to those byproducts, it assigns them to the primary use.
Why not use fibres in concrete Flax Banana Glass Hemp
I put plastic in cement
Very uninformed with geopolymers theres over 40 years of research and many kinds of materials that you can use
So tired of the unwarranted focus on CO2.... The sun controls the earth's climate. The one GHG that overwhelmingly influences climate is water vapor NOT CO2 or Methane. Most plant life breathes in CO2 and exhales O. CO2 is needed and not to be reduced from the ranges we have seen. One volcano emits tremendous amounts of CO2, but volcanoes that affect climate most do so by shading the earth not by CO2.
Concrete's CO2 contributions are insignificant relative to volcanoes and the sun.
Furthermore, longevity of a structure spreads on the emissions over the years.
Focusing on durable concrete that doesn't fail is the best practice.
#Tyler I like koke kola. We like concrete because it can be used to build lotsa strong structures but we are looking for cement/s 💕that isn't a carcinogen (hexavalent chromium - Google) 🤮? @NoaKirel LA SF 💕 #Potential #CANCER #WARNING