Posted on 11/15/2007 2:53:39 PM PST by Squidpup
Innovations in methods and ingredients have made possible lightweight bridges, color-changing buildings, and furniture created from this efficient material
Concrete is ubiquitous in the modern world, yet most people don't give it a passing thought. Why would they? It may be the most consumed substance on earth after water, but the stuff of pavements and parking garages is also a bit dull—or so most of us thought. In fact, innovations in the science of concrete have enabled architects and designers to achieve remarkable feats that would have been impossible in earlier years—everything from ultra-thin bridges spanning hundreds of feet to furniture made from lightweight blends.
One of the big factors behind the resurgence of concrete is the environmental movement. Scientists and architects have rediscovered concrete's potential to save energy, since its thermal efficiency reduces the need for air conditioning and heating. But with this reawakening has come demand for more lightweight, durable, and aesthetic concrete by the designers who use it. ..SNIP..
(Excerpt) Read more at businessweek.com ...
I remember back in the early 70s there was a bunch of stories about people making boats out of concrete. Haven’t heard much about them since.
Congressman Billybob
THEY MADE BOATS OF CONCRETE IN WWII!......We have one here in Ft. Walton Beach..........
My alma mater, SDSM&T.
When I think of “Feats of Concrete” I think of what Hillary has in plans for her political enemies, should she win... ;0)
I'll take a union crew over a crew whose dialog begins with "Si, Señor".
It drives me crazy when I hear people refer to concrete as cement. Cement is a powder.
Sorry, concrete must be banned for the good of Mother Gaia. It emits CO2 when it cures.
Pycrete - Interesting stuff. They thought about making massive floating battleships out of it in WWII.
Pykrete is a super-ice, strengthened tremendously by mixing in wood pulp as it freezes. By freezing a slurry of 14 percent wood pulp, the mechanical strength of ice rockets up to a fairly consistent 70 kg/sq cm. A 7.69 mm rifle bullet, when fired into pure ice, will penetrate to a depth of about 36 cm. Fired into pykrete, it will penetrate less than half as far — about the same distance as a bullet fired into brickwork. Yet you can mold pykrete into blocks from the simplest materials and then plane it, just like wood. And it has tremendous crush resistance: a one-inch column of the stuff will support an automobile. Moreover, it takes much longer to melt than pure ice.
http://www.cabinetmagazine.org/issues/7/floatingisland.php
bmflr
Gadzooks! 
You need to go back further to find out ships were being made of concrete way before the 1970s!
Check out A Brief History of Concrete Ships and Wikipedia Concrete Ship article.
There are sailing yachts made out of concrete.
I think a lattice is formed , then sprayed. A Gunnite type construction.
I do question the thermal insulating ability of concrete though.
I know from living in S. Fla. where most homes are CBS construction that a west facing wall got hot in the interior and stayed hot for hours after the sun set.
The monolithic domes don’t. The form is set up, inflated, lined with polyurethane foam and then concrete.
CHeck out thier site, some pretty cool buldings.
It was a fun thing to do to FNG’s at Cementer’s School in Duncan, OK. A little coffee packet stirred into their samples of quick curring cement they were getting familiar with...was supposed to set in 90 seconds of being static. To be used in squeeze jobs.
But no, I'm not going to lug around a 100-pound credit card.
However, the Pantheon is an incredible structure and worthy of an architectural class all by itself. Sadly few architects could even identify Vitruvius today.
Trick question?
The Pantheon is worth a trip to Rome all by itself. Probably the most beautiful and impressive work I saw when there.
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