This is unforgivably dumb. The problem with unreinforced concrete is it has no strength in tension, which means the only way you can build with it is to stack it. Which is great if you want to build, say, the Parthenon but not so great if you want to build, like, a bridge. Rebar for reinforcing concrete is generally used for durability and flexibility. Know how after WWI everything concrete was rubble? But after the war in the Balkans there were a bunch of demolished concrete structures still standing? Rebar. Also good for earthquakes. As far as the whole "will last forever" thing, nobody really took that seriously. Rebar-reinforced concrete is good for the useful life of most buildings, which is generally assumed to be well under 100 years. Meanwhile all the problems outlined in the article with rebar reinforcement have been handled by prestressing which is pretty much Building 101 since the '50s. So, yeah. This article makes a lot of sense if it's 1916. It's not, though. It's 2016.
I disagree. I don't think rebuilding everything every 50 years is very sustainable, especially considering the very high CO2 emissions when making cement/concrete. So of course using plain concrete is no solution, but looking for better solutions is very much needed IMHO.
They mention a couple potential alternatives in the article.
Yeah. "mud brick" and "rammed earth."
Cost reflects sustainability. These green techs are often very cute, but more often than not they drain so many resources that they will ultimately cost us more total pollution than the cheaper often. In 100 years tech advances so far that rebuiding saves more energy and time in the long run than leaving the building does.I don't think rebuilding everything every 50 years is very sustainable
http://www.concretenetwork.com/concrete/repairing_bowed_basement_walls/carbon.htm They are starting to use more carbon fibre and fiberglass mesh as a reinforcement medium as well.