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Researchers Make Bendable Concrete
karvind writes "PhysOrg is reporting that scientists from University of Michigan have developed a new type of fiber-reinforced bendable concrete. The new concrete looks like regular concrete, but is 500 times more resistant to cracking and 40 percent lighter in weight. Tiny fibers that comprise about 2 percent of the mixture's volume partly account for its performance. Also, the materials in the concrete itself are designed for maximum flexibility. Because of its long life, the Engineered Cement Composites (ECC) are expected to cost less in the long run, as well." Michigan roads must make the perfect test cases for this stuff, and I look forward to their improvement.
Now finally we can see buildings that bend and shift better under harsh weather conditions such as wind and rain.
The benefits of this extend greatly beyond that as well however.
It will be intresting to see where this goes...
Michigan roads must make the perfect test cases for this stuff
Except that roads crack because water infiltrates under the surface and freezes over. I don't know many material, even 500x stronger concrete, that can withstand the force of expanding freezing water.
I think the material is more targeted toward seismic-proof constructions.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
I wonder if this new concrete may enhance the concrete submarine programme for deep submersibles.
Being in something with a bit more toughness, and better tensile strenght might be more reassuring. A little less like going to sea in an eggshell.
If the material won't bend/stretch at all, it might shatter, this new elastic concrete supposedly kand bend at least a little, so it could withstand the freezing expanding water. At least I think that the freezing expansion is not enough to stretch the new concrete to it's limits.
-Is the meaning of life vanity, or is vanity the meaning of life?
That would be SO much funnier if this were the right time period, if the article had to do with transparent aluminum, and if you had a scottish accent.
If you like what I've said here, and want to read more, go to http://www.krillrblog.com
why? because nobody makes the first jump. (shameless matrix refrence)
this one can be solved with bending - Bender Bending Rodriguez
The article fails to state whether the ductility of the concrete results in elastic (returns to its original shape when load is relieved) or plastic (stays in the shape you bent it) deformation.
One would hope for the former, since structures made out of this material may look strangely 'bent' over time if it readily undergoes plastic deformation.
And one last note: is this material going to be more cost-effective than steel?
I'm Trappped at Berkeley.
Fiber reinforced materials have been around for years. Carbon and glass fiber reinforced polymers are used in many everyday applications without harm. The problem with asbestos was its crystal structure and cleavage planes, which enabled it to break down into very small (micrometer scale) fibers that were easily inhaled.
The above comment is about as insightful as saying "Cotton fiber? That seems eerily reminiscent of asbestos, better not wear clothes!" or "AIDS medicine? Wasn't thalidomide also orally available in pill form? Better not give it to pregnant women..."
Making the moon less necessary since 1998.
...can it withstand the impact of a jet airplane?
No, but because of it's bendability, it can actually dodge incomming plains.
because the concrete is thinner, not because the concrete is lighter. This discerned from RTFA. We poured a pad for a picnic pavilion at the yacht club using concrete that is reinforced with polyethylene fibers. It allowed us to pour a large pad that will not crack without having to use tiebacks. Which brings to mind something I've often wondered about...
With concrete, when it's pre or post stressed in compression, it's much less likely to crack. Traditionally this is done by tensioning the steel prior to pouring or tensioning cable or rod 'tiebacks' after partial curing. Now this is very nice but... It should be possible to engineer a fiber that will shrink as it ages and bonds well as an aggregate. If the shrink time could be matched up reasonably well with the cure time of the concrete it would simplify many types of construction.
Concrete was the first material that was used in the construction of mass use roadways back in the early days of the automobile as asphalt hadn't been discovered yet. Theres a very good chance that the concrete roads you drive on today were laid back in the 40s and early 50s. But concrete was always expensive to use, and required extensive preperation of the ground in order to pour it. So it was a slow and tedious proces, and not many cities could not afford to have more than one crew going at a time.
When it was discovered that Asphalt, a by-product of oil refining, could be mixed with a small sized aggregate *gravel* and basically smooshed ontop of any roughly prepared surface to create a roadway, well that was the end of using concrete. Most concrete projects were abandoned overnight and roads started being laid at a fraction of the price and at triple the speed.
The one caveat is that in Northern Areas it was discovered that asphalt roadways were not holding up as long as their concrete breathern. Many asphalt roads were having to be torn up and replaced every other year due to extensive freeze damage. Many cities went back to using concrete for their roads, until better techniques of preparing the roadbeds were discovered. Which were to compress and smooth the roadbed as much as possible, then lay a barrier layer of aggregate *gravel* on top of that to help with drainage and settling, then to finally slope the finished road from the middle to the edges for increased water run-off.
World Trade Center made of bendable concrete: 262m $US
747: 5m $US
Razor Blade to hijack plane: 2.95 $US
The look on Osama's face as the plane bounces off the building: priceless.