Cracking Concrete's Code

ScienceNOW Daily News ^ | 2 February 2007 | Robert F. Service

[AlexW]

"stuffed into the trunk of a Toyota that was subsequently sent to a car crushing plant."

Wow, just as in Goldfinger, but Bond got away, as always.:))

[Thermalseeker]

It's easy to see the new particles/new methods failing under vibration or stress over time.

From my experience, having watched literally thousands of foundations for cell towers be poured, I've come to the conclusion that they still haven't got the original formula figured out yet, at least not consistently. I've seen several dozen over the years that had to be abandoned because they never reached the proper break strength, and thus the tower could not be stacked.

[printhead]

"C-S-H particles that were either randomly arranged or ordered like oranges on a store shelf", sounds a bit like ICE-9 to me.

[Conservativegreatgrandma]

Fifty to one hundred years? I was in Ephesus and saw a concrete dome 2000 years old. Part of it is still standing.

[Robert A Cook PE]

Fifty to one hundred years? I was in Ephesus and saw a concrete dome 2000 years old. Part of it is still standing.

8<)

but when I'm on a bridge, I want ALL of it to still be standing - at least until I get off the top of it.

Or from under under the bottom of it.

[TChris]

Estimates indicate that the energy used to create concrete accounts for 5 to 10 percent of the world's CO2 emissions.

I'm longing for the days when CO₂ won't--bafflingly--be referred to as a pollutant any longer.

This is more ludicrous than the enviro's treatment of DDT!

[ccc_jr]

This one is around 1,700 years old and is doing just fine. Its quite a sight if your ever in Rome.

[Conservativegreatgrandma]

You're absolutely right. I've been there--twice. I've also seen a very good documentary of it on the History Channel.

Your example is far better than mine and I should have remembered this.

[sit-rep]

Up this early every morning... Got to make the daily bread!!

Wake at 5, check Truline Forum, make the rounds to about 7-8 other forums and out the door at 0545 sharp. Got it down to a science babe!

[endthematrix]

Not only C02, but water runoff. I can't help but remember a local lake was filled with dead fish, because off polluted (IIRC salted) runoff from a large mall parking lot. Also, our Deep Tunnel project in NW Illinois can dump millions of gallons of untreated runoff into Lake Michigan.

Your post reminded me of the Talking Head's tune, (Nothing But) Flowers.

[Fierce Allegiance]

Civil engineers ping

Ahh, a FReeRepublic topic near and dear to my heart!

Lemme know if you want on the ping list.

[Fierce Allegiance]

Seen quite a few laborers get hernias trying to move 2" slump concrete.

Gotta have the HRWR! What a loabor (and laborer!) saver! Chuck an egg in the mixrt, 60 spins, good to go! Turn a 4 slump mix into an 8" slump, with NO negative effects on the strength. It just kicks a little faster.

[Fierce Allegiance]

Microsilica fume (GGBFS) is the best damn thing in concrete technology since water and lime! Really helps strength, and chloide attack resistance.

[skinkinthegrass]

WOW!...really enjoying the thread. :D

[Fierce Allegiance]

LOL!

I have few loves in my life, but put everything I have into them. Beer, politics, my daughters and construction. Not necessarily in that order.

[Robert A Cook PE]

Well yeah, sure it's been around a long time.

Big deal.

When is the contractor gonna get around to fixin' that big hole in the roof?

(And I "know" the big sports arena in that town has not flooded its ice hockey arena since the early 00's .... When THAT gonna get fixed?

[The SISU kid]

Us suckers in Washington State are still paying for this hunk -o-concrete and it aint even there no more!!!!!

8^(

[Conservativegreatgrandma]

LOL

[NewJerseyJoe]

Concrete -- made from the best stuff on Earth. (long before Snapple)

Construction automation using inflatable structures to make concrete shells:
http://www.binisystems.com/ca.html

[Grizzled Bear]

Recycling Hoffa's carbon footprint was easier when his actual footprint is much smaller ....
__________________________________________________________

That explains strange behavior of, and demonic laughter emanating from, my Mom's Pinto!