On Jun 16, 11:20*am, The Daring Dufas
wrote:
On 6/15/2011 2:29 PM, DerbyDad03 wrote:





On Jun 14, 11:27 pm, Harry *wrote:
On Jun 14, 10:18 am, *wrote:

On Jun 14, 6:33 am, "Bob-tx"No Spam no contact *wrote:

Hope this isn't ot - these could be used for a garage, shop, chicken house,
etc.
Bob-tx

http://www.wimp.com/concretetents/

But, all that glitters is not plastic - read below

LONDON (AlertNet) - Two British engineers have scooped a global innovation
award for an inflatable concrete tent, designed for rapid deployment in
disaster zones, but aid workers differ on its practical viability.
The inventors, Peter Brewin and William Crawford, say they saw a need for
the structure given the inadequate protection provided by tents in the
aftermath of disasters such as the Pakistan earthquake.
'With shelter and medical facilities it is possible to rebuild shattered
communities from day one of a crisis,' they said in a statement.
The tent, made from fabric impregnated with concrete, can be put up by an
untrained person in 40 minutes. It takes 12 hours for the concrete to set,
but once done, the tent can last for up to 10 years.
The two designers, both 26, developed so-called Concrete Canvas during an
industrial engineering course at the Royal College of Art in London. Their
efforts were rewarded on January 26 at a ceremony in New York with the
presentation of the top prize at the Saatchi& *Saatchi Award for World
Changing Ideas.
Media reports say the invention has attracted interest from the United
Nations and several international humanitarian agencies.
JUST ADD WATER 'If this was available now, we would buy 10 today,' Monica
Castellarnau, a programme director at M'decins Sans Fronti'res, was quoted
as saying by Wired News. Its combination of ease of assembly with durability
has also drawn praise.
The logic of Concrete Canvas is simple. Each unit ' weighing 227 kg (500
lb), making it light enough to transport by plane or truck - comprises an
inflatable plastic inner bubble, wrapped in the treated fabric and packed in
a plastic sack.
To deploy the tent, the sack is first filled with 145 litres (32 gallons) of
water, which is absorbed by the cloth. The sack is then cut open, the tent
is unfolded and the plastic bubble is inflated. The canvas then moulds
around the bubble and sets to form the solid infrastructure of the tent.
The finished shelter covers some 16 sq meters (172 sq feet) of floor space
and the cost per unit is estimated at '1,100 ($2,100).
But some aid officials are not convinced.
'At first sight it looks marvellous,' said Rishi Ramrakha, a logistics
officer at the British Red Cross Society. 'But the real practicalities look
a bit difficult.'
According to Ramrakha, there are several central problems. First, the unit
is too heavy to be carried easily into areas where there might not be access
for aircraft or trucks. The second is the amount of water needed to erect
each tent.
'Where are you going to get 145 litres in a disaster zone?' he asked..
Experts also point out that displaced populations are accommodated in
temporary shelter because they will eventually be encouraged either to go
back to where they came from, or to make homes and a new life in a better
place.
The construction of permanent structures, particularly in conflict zones,
could hamper that process, they say.

The article says "To deploy the tent, the sack is first filled with
145 litres (32 gallons) of *water, which is absorbed by the cloth. The
sack is then cut open, the tent is unfolded and the plastic bubble is
inflated"

The video says the tent is inflated first then saturated with water.

The video method seems to make more sense since I can't see how a
folded up tent is going to absorb water evenly.

What happens if it rains for few days as the concrete is setting?- Hide quoted text -

- Show quoted text -

Probably nothing. *Concrete can be poured and will cure under water.
I did that with a very small irrigatin dam. *Had to put the concrete
down a big pipe or it would mix with too much water on the way down.

Harry K- Hide quoted text -

- Show quoted text -

How does it mix with too much water on the way down but not mix with
too much water once it's actually down?

As the dumb jock once said about a Thermos keeping hot stuff hot and
cold stuff cold:

"How does it know?"

You gave the dumb jock too much credit, he actually said "How DO it
know?" ^_^

TDD- Hide quoted text -

- Show quoted text -

Well, when I heard the version where "How do it know?" is used, the
term "dumb jock" wasn't used to describe the speaker.

The term used was, shall we say, a bit more racially descriptive.

I chose to remove the racial overtones in both the description of the
speaker and in the punchline.