Posted on 09/27/2018 6:26:49 AM PDT by BenLurkin
To Rice materials scientist Rouzbeh Shahsavari and graduate student Sung Hoon Hwang, the spheres represent building blocks that can be made at low cost and promise to mitigate the energy-intensive techniques now used to make cement, the most common binder in concrete.
The researchers formed the spheres in a solution around nanoscale seeds of a common detergent-like surfactant. The spheres can be prompted to self-assemble into solids that are stronger, harder, more elastic and more durable than ubiquitous Portland cement.
"Cement doesn't have the nicest structure," said Shahsavari, an assistant professor of materials science and nanoengineering. "Cement particles are amorphous and disorganized, which makes it a bit vulnerable to cracks.
But with this material, we know what our limits are and we can channel polymers or other materials in between the spheres to control the structure from bottom to top and predict more accurately how it could fracture." He said the spheres are suitable for bone-tissue engineering, insulation, ceramic and composite applications as well as cement.
(Excerpt) Read more at phys.org ...
He said increasing the strength of cement allows manufacturers to use less concrete, decreasing not only weight but also the energy required to make it and the carbon emissions associated with cement’s manufacture.
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My prediction is this will never be commercialized.
So what if it’s as slippery as ice. It will crack in pretty patterns.
The company I work for makes a material that uses very similar technology. Different sizes of beads give the product some really cool handling characteristics.
However, I don’t see it for something huge scale like concrete. Concrete is essentially the mixing of a bunch of natural materials with a small amount of manufactured admixtures for specific characteristics.
I can’t imagine how you would scale up sphere production and ship it globally to replace naturally occurring products that are merely dug out of the ground, heated, crushed and packaged
Concrete bubbles are too heavy to float here on earth.
We were using 3M Scotchlite glass spheres to make floating 10,000 PSI concrete in the early 1990’s for our concrete canoes.
I’ve seen actual lead balloons that float in air.
Years ago I spilled some glass beads (for bead blasting) on the concrete floor. I made the mistake of stepping on them. There was a moment of, “This is gunna hurt.” and it did.
Failed to mention that it will greatly increase cost.
Concrete with river rocks (roundish) was abandoned long ago for crushed rocks (sharp corners). The sharp corners stop adjacent rocks from sliding past each other (until the corners crumble and the concrete cracks). Rounded rocks slide easily and crack at much lower loads.
The unmentioned factor is cost. $400/lb concrete may be useful for bone replacements...
>... for our concrete canoes. <
The existence of such things make me smile.
This is fascinating technology. I could see it as an additive of concrete (building material). I do not see how it does the work of cement, however, to bond the aggregates.
Additives to the 1/2/3 common concrete mixture is common- like fiberglass, Styrofoam ( used in shooting ranges!) and poly beads of varying shapes is not what these idiots are talking about- seems they are replacing relatively inexpensive Portland cement ( CaO, SiO, AlO) with petroleum based stuff ( polymers and carbon nano stuff).
Likely will be IR degradable and unstable in many environments, just what we need.
Concrete has lasted since the Romans first used it in the 1st century BC ( yes, Before Christ, not BeforeCommonEra).
Concrete is a fascinating CE topic.
[Years ago I spilled some glass beads (for bead blasting) on the concrete floor. I made the mistake of stepping on them. There was a moment of, “This is gunna hurt.” and it did.]
Had the same experience with water softener resin. Almost went through a wall. LOL
I poured a slab for a stoop in front of a door with concrete and a fiber additive. Hasn’t cracked yet. (4 years) The last one cracked with 2 years. Quite impressive.
If I knew anything about chemistry, I would say that limestone is CaCO3. And that cement is produced by causing limestone to dissociate under heat into CaO and CO2. So much would agree with the statement above.OTOH if I knew anything about chemistry I would say that when cement sets, the reverse reaction occurs and CaO and CO2 from the atmosphere combine to form CaCO3. But that can’t be right, because the article clearly indicates that using cement is a net addition of CO2 to the atmosphere.
“[Years ago I spilled some glass beads (for bead blasting) on the concrete floor. I made the mistake of stepping on them. There was a moment of, “This is gunna hurt.” and it did.]
Had the same experience with water softener resin. Almost went through a wall. LOL”
The rural equivalent of this would be soybeans. We had a large spill in a parking lot once and the cleanup effort was nearly slapstick.
That being the case, you might really enjoy this: http://www.concreteships.org/ships/ww2/
I guess lead foil counts, so, yeah.
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