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What is Concrete?

34 pointsby mikecarltonalmost 10 years ago

7 comments

dstyrbalmost 10 years ago
Cool stuff -- author doesn&#x27;t mention that Roman cement had a usability life of &gt;2000 years, while Portland cement starts to degrade after 50 years (for rough harbor usages).<p><a href="http:&#x2F;&#x2F;www.bloomberg.com&#x2F;bw&#x2F;articles&#x2F;2013-06-14&#x2F;ancient-roman-concrete-is-about-to-revolutionize-modern-architecture" rel="nofollow">http:&#x2F;&#x2F;www.bloomberg.com&#x2F;bw&#x2F;articles&#x2F;2013-06-14&#x2F;ancient-roma...</a>
banealmost 10 years ago
One of the really surprising things when you visit the Colosseum in Rome is how <i>modern</i> a structure it feels. Rather than ruins, it feels more like a construction site, a half-finished stadium for some up coming Olympics or World cup.<p>It&#x27;s not just two Greek amphitheaters dug into facing hillsides...it&#x27;s something on a completely different level.<p>All this despite being left in complete, abandoned ruins for something like a <i>thousand</i> years. Then damaged in earthquakes, stripped of stone (probably also concrete blocks) for other construction, legend has it&#x27;s been used by monastic orders, as a wool factory and other crazy uses.<p>This isn&#x27;t modern reinforced concrete, it&#x27;s <i>just</i> concrete.<p>If you wonder around Rome you come across possible the pinnacle in concrete work in human history, the Pantheon. I&#x27;ve heard that we <i>still</i> don&#x27;t know how they produced the dome, another nonreinforced wunder construction that&#x27;s survived for millenia. Again, survived earthquakes, wars, and other uses, and again a huge structure that feels amazingly modern in size and scope.
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lingbenalmost 10 years ago
it still boggles my mind that Rome has working sewers that were constructed more than 2000 years ago and there is every indication that they will last another 2000 years of continuous use<p><a href="http:&#x2F;&#x2F;www.bbc.co.uk&#x2F;programmes&#x2F;b05xxl4t" rel="nofollow">http:&#x2F;&#x2F;www.bbc.co.uk&#x2F;programmes&#x2F;b05xxl4t</a>
andrewlalmost 10 years ago
The book <i>Stuff Matters: Exploring the Marvelous Materials That Shape Our Man-Made World</i> has a chapter on concrete. The self-healing concrete was completely new to me. Definitely worth a read, and not just for the concrete chapter:<p><a href="http:&#x2F;&#x2F;www.goodreads.com&#x2F;book&#x2F;show&#x2F;18222843-stuff-matters" rel="nofollow">http:&#x2F;&#x2F;www.goodreads.com&#x2F;book&#x2F;show&#x2F;18222843-stuff-matters</a>
ubasualmost 10 years ago
See the concrete canoe competition:<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Concrete_canoe" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Concrete_canoe</a> <a href="http:&#x2F;&#x2F;www.asce.org&#x2F;concrete-canoe-photo-gallery&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.asce.org&#x2F;concrete-canoe-photo-gallery&#x2F;</a>
bbcbasicalmost 10 years ago
Another interesting property of unset concrete is that it can burn your skin due to alkalinity.
IgorPartolaalmost 10 years ago
Meta comment: I often times find great articles on Gizmodo. While other Gawker sites like Lifehacker are more mediocre, Gizmodo often features interesting and more in depth posts like this one.