Welcome to European Tribune. It's gone a bit quiet around here these days, but it's still going.
A quick reply (because of work!)... And I might not have understood the question ?!
Either you design a new building with anti-sysmic care, mostly architectural answers (volumes, weight, facades, etc.).
Or you intervene on existing buildings, having been stressed by a recent earthquake, but still usable (hair-cracks, but no real displacement of structure). In this case, instead of using timber or steel beams, a structure reinforcement with these new concrete can be designed.
Instead of beams, it would more be a complete "frame cube" (4 porticos) that could be set in each volumes (rooms). It could have the size and looks of some thick baseboards (ceiling and floors), thus allowing the use of those living spaces...
More then 30 000 flats are still stressed in Algier and that's as much families that are in danger, as the few new buildings that are built are for the thousands families that have no homes since the last earthquake.

Those concrete frames can be prefabricated and used just as steel is, either by clipsing (the concrete can be as thin as 2 mm) or by using the "nut and bolts" system (those being also in concrete)...

I'll get a more precise answer on saturday :-)

"What can I do, What can I write, Against the fall of Night". A.E. Housman

by margouillat (hemidactylus(dot)frenatus(at)wanadoo(dot)fr) on Fri Nov 25th, 2005 at 01:58:50 AM EST
[ Parent ]
You understood perfectly!

2mm frames?  As thin as that!?  How surprising!  I look forward to your "more precise answer."  

And now, I too, must get to work.

She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre

by ATinNM on Fri Nov 25th, 2005 at 12:10:31 PM EST
[ Parent ]
Without  really being more precise, there's another way to use these concretes... By projection!
In fact these new "high-tech" concretes work best in thin layers. A projected layer of about 5mm and 1 cm in the angles of a room would give you a fairly decent ductile shell. You could then clad it with plaster (or whatever) as it would be a bit "hairy"...
Of course it works best for small rooms of 5m to 6m span. And it depends of how the original building was built !

This projection technique is used for example on existing posts when you want to add some levels to an existing building and that the foundations are good enough.
You spray this concrete as an outward layer of the existing post, boosting it to the desired section, while people are still working in the office, the works being behind plastic sheets...

In conclusion, there are numerous ways to achieve the re-furbishing of stressed buildings. The "meccano" one being the less obnoxious in use and time and quantities... So surely the cheapest!

Two millimeters is quite easily obtained in a prefabrication controlled process (pressure molds).
Some, today, are thinking of designing window frames with this concrete. They would be as thin as the steel one's but with no corrosion and with a thermal resistivity nearer to wood. And we could leave aluminum to planes and boats...!

"What can I do, What can I write, Against the fall of Night". A.E. Housman

by margouillat (hemidactylus(dot)frenatus(at)wanadoo(dot)fr) on Sat Nov 26th, 2005 at 05:31:23 AM EST
[ Parent ]


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