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Why do we bother with heavy construction materials in earthquake zones? No matter how strong you make them, there's always an earthquake big enough to break your structure if you wait long enough.
Instead, build single-story buildings out of Styrofoam in a single cast shape. Cast in the wiring and
plumbing as well. You could build them in a factory and simply place them by helicopter. They'd be waterproof, and last more or less forever.
Wind might be an issue. I'm thinking a rounded shape (like an igloo), with a thick bottom that's bolted to a foundation.
EPU
http://www.freemans...shapemodelingan.htm One source of middling to higher density polyurethane foams. [MechE, Feb 20 2014]
reinforcing bars, who needs them?
http://www.architec...tect/580492.article Japan architect caught out.. [not_morrison_rm, Feb 22 2014]
Styrofoam House
http://www.homebuil...d-concrete-formwork The use of Styrofoam as a construction material is well known to already exist. [xenzag, Feb 23 2014]
[link]
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You know, this is not such a stupid idea. |
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// I'm thinking a rounded shape (like an igloo), with a thick bottom
that's bolted to a foundation. // |
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Manufacture on-site using polyurethane foam ? |
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Hi Worldie, long time no see. Anyway, I was thinking,
after you finish your ice cold beverage in your
styrofoam cup, you could just smush it in to your
living room wall and think "wow...reinforcement". |
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Sounds good, but I would not want to be inside one of these things if there were a fire. |
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should be useful in a flood too... just make sure the
weight distribution means that it floats upright |
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//Burglars would only need a hot-wire cutter// they
only need scissors with those uPVC doors. A brick for
a regular window, an electric toothbrush, a
screwdriver and half an hour for a regular Yale lock. |
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Love the dome homes link. Exactly that, but built all as one piece and pre-wired and plumbed. |
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I don't think a burglar would even need a hot-wire cutter, just a car. But I suppose that's true with regular homes as well. |
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[bliss] Now I'm thinking of a built-in refrigerator. |
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// A brick for a regular window, an electric toothbrush, a screwdriver and half an hour for a regular Yale lock. // |
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Breaking glass makes noise. I think a hot wire cutter is very quite and could be quite fast. On the other hand, it should be possible to embed a wire mesh grid in the foam to detect cutting. |
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It really comes down to what you're defending against. If you're worried about home invasion, but have peace of mind living in a brick house with bars on the windows and a lock on the door that can't be opened from the outside, then styrofoam would be a very poor alternative. If you have a house with a full height decorative window panel next to the door protected by a glass breakage detector (common where Ilive), then I'm sure we could come up with a way to make the styrofoam house just as "secure". |
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Choose one of (a) risking having your possessions stolen, or (b) dying
under the collapsed rubble of your house and smashed-up
possessions ... |
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//Well its *quite* stupid. Burglars would only need a
hot-wire cutter and for anywhere with snow you'd
get flattened.// |
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True, and yet at the same time completely wrong. |
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No reason you couldn't clad the foam in a thin
layer of stainless steel. It would only increase the
average density a little bit, so falling wouldn't be
much worse, it would make the structure much
more impact resistant, much less vulnerable to UV
decay, and much harder to cut through. (I'm
figuring just thick enough that you couldn't punch
through it easily with a screwdriver, probably as
little as 0.5mm, maybe less). |
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It would also make cleaning up the exterior a job
for a ladder and a scouring pad once a year or so. |
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And depending on the design and the foam
density, I wouldn't worry to much about crushing
under snow load. Worst case you go to expanded
polyurethane (see link), which is available in
densities ranging from similar to styrofoam cups all
the way well up to many common hardwoods. The
trick would be to find the right balance between
collapse safety and density. |
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it wouldn't be difficult to mould in/cut some galleries
and pump a little network of concrete through. A
nice geodesic structure would work. |
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I have to admit, this seems like a pretty good idea on
its face, and I'll
award a bun for creative thinking. But there are some
pretty major
drawbacks to styrofoam construction. |
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For one thing, it's actually not all that useful for
earthquake safety.
You'd only be able to build a single story house out of
styrofoam, and
the vast majority of structures that collapse in
earthquakes are
multistory apartment buildings. At least, that's the
accepted wisdom
here in L.A.immortalized by C.W. McCall as
Shakeytown. Many of the
single story houses around here have been around for
the better part
of a century by now and are still as strong as the day
they were built,
if not stronger thanks to earthquake-proofing
retrofits. But every big
earthquake it seems that at least a couple of shoddily
constructed
apartment buildings with ground-level garages
pancake, and that's
where the real danger is. Styrofoam, unfortunately,
would not be
suitable for such construction. |
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The other problem is that Styrofoam isn't really that
lightweight when
you have a lot of it. A moderately dense Styrofoam
weighs on the order
of 32 kg / m^3. The room I'm currently in is roughly
4x7 meters, and
the roof is about 30cm thick (in case you're wondering
how I figured
that, the roof has a recess for a skylight about a foot
deep). That roof
would weigh about 270kg. Not something I would want
falling on me,
and that's not even counting the weight of the walls,
should they
collapse as well. |
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Basically, you don't want to count on the structure not
injuring
someone when it collapses. And then there's the
problem of rebuilding
the whole house when it does collapse, which is
expensive, time
consuming, and really just a royal pain in the arse. |
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I could almost see this as suitable for industrial
facilities and the like in
areas subject to hurricanes or tornadoes, where the
structure is pretty
much doomed no matter what. But earthquake-proof
construction is
very, very effective, as evidenced by the fact that Los
Angeles and San
Francisco are still standing (at least, for the present). |
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Just because people are doing it doesn't make it a
good idea. While it may be possible to build single
story structures out of Styrofoam, it's not necessary to
do so because those aren't the type of buildings that
are at risk in an earthquake. So my argument isn't
pointlessyou just missed the point. |
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To make it painfully obvious what my point is (for
those of you who apparently missed it), the answer to
the question of why [] we bother with heavy
construction materials in earthquake zones is
because heavy construction designs and materials hold
up very, very well in earthquakes for the type of
construction this idea is suggesting, which is a pretty
strong argument for using them. Why is it better to do
things cheaply and put people at risk, only to have to
rebuild when things ultimately go pear shaped and
potentially kill the occupants? |
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Yes, but no bugger is actually buying them...and recent(ish) scandal of construction company leaving out some the reinforcing bars in a hi-rises to save a few pennies....see linky |
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Have you seen styrofoam burn? And it puts out highly
toxic gasses when it does so... |
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I take it candles are not recommended as source of light? |
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Yes of course. I am aware of that and have seen them at trade shows. However, the idea is there, to NOT fill them up with concrete, but simply glue the polystyrene blocks to each other, then pump more polyisocyanate (or whatever) into the cavities, thus forming an entire structure out of expanded foam. I still say it's a death trap re fire. It may even leach out deadly fumes, but not sure about that. |
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It's easy to make polystyrene fire retardant. |
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You might find your house being dissolved around you. The acetone
that is the main ingredient of nail-polish remover will destroy a LOT
of styrofoam. Gasoline is nice, too. |
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[ytk] The idea stemmed from considering very-long-term construction. Our buildings are generally designed for a 100 year earthquake. But suppose you wanted to build for a 1,000 year earthquake? Just 300 years ago a 9.0 megathrust quake dropped the Washington State coast by several feet. Wiki tells me this size quake causes "severe damage or collapse to all buildings", and an 8 causes "moderate to heavy damage to sturdy or earthquake-resistant buildings". There are no current structures I know of that are designed to survive this, yet there's an 8.0+ about every year somewhere in the world and a 9.0 once every 10 to 50 years. |
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I chose 1-story because that would be the most likely to survive. But unless it's thick steel, enough shaking would topple most any structure. So I went with Styrofoam. |
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Building for a 1,000 year earthquake is a losing proposition. Materials science
and construction standards are improving so rapidly that your best bet of having
a structure survive an earthquake that rare is to regularly update your
structure, or to simply rebuild once it's no longer cost effective to do so. Keep
in mind that it's not just that your structure has to be able to withstand a 1,000
year earthquake when it's built, but it has to last long enough to be just as
strong when that earthquake finally does occur, which could be centuries from
now. Long term deterioration will surely degrade the structure's ability to
withstand earthquakes. |
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I wonder if building a rigid single-story structure out of
things like steel and laminated glass and then setting it on
a crushable, replacable polystyrene foundation would be
worth looking at. If you weld a pad eye to the peak of the
structure a crain could lift it up and set it onto a new
foundation. |
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Unless they fall into cracks in the ground,
and as long as nothing falls on them, vehicles
do pretty well in earthquakes. The tyres and
suspension buffer and damp the oscillations. |
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A camper/RV parked on a reinforced
concrete plinth, away from big trees and
utility poles, has a lot going for it. |
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For a start, it can operate independant of
external services for several days. It also
provides transport (if the roads survive). |
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It is proof against quite severe environmental
conditions; extremes of temperature and
precipitation. |
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So a survival strategy in earthquake areas
might look like: |
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1. All services run just above ground level in
fenced, protected corridors. |
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2. All dwellings consist of a semi-fixed
(mobile home) portion coupled to an
autonomous RV (Think Apollo 13, Command/
service module and LEM) |
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3. All non-dwelling buildings are lightweight
trailer-moveable modules conforming to ISO
container form factors, on small but
functional solid-tyred wheels with a basic
"suspension". |
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Your species needs to grasp the fact that
constructing population centres within the
activity footprint of tectonic and volcanic
active regions is a Bad Thing. |
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1. Survey all the "at risk" areas and mark
them on maps. |
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2. In these areas, demolish or remove all
large structures and replace them with vast
trailer parks as per design. |
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3. Deal with objectors by summary
execution. This is entirely ethical, since if
they are left undisturbed they are inevitably
going to be killed or suffer severe and
expensive injury. It is therefore an act of
kindness to eliminate them, and benefits
your species gene pool by removing those
organisms which exhibit self-destructive
stupidity. |
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Styrofoam is bulky to move around. Could one build
such a structure by laying down expanding
polyurethane foam over a plastic or metal mesh? I
think UV resistance is a problem for polyurethane
but a coat of paint or panels would fix that. |
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//1. Survey all the "at risk" areas and mark them on
maps.// |
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I challenge you to find a place on the globe that's
not subject to some sort of potentially devastating
natural disaster. There may be a few here and there,
but the overwhelming majority of spotsand nearly all
of the spots one might wish to liveface some kind of
mortal peril. |
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// some sort of potentially devastating natural disaster // |
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The specific threat to be mitigated is stated as earthquake. |
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It is correct that the "RV" solution would perform poorly against
fire, flooding, high winds or tornados, molten lava or the Big Bad
Wolf. But none of those threats were in the design brief. |
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// someone in Alabama is going to read this /
/ |
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We saw what you did there. Someone "in"
Alabama, not someone "from" Alabama
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