# 7281 bydsw_s@... on Nov. 26, 2005, 2:46 a.m.
Member since 2021-10-03
ANTIcarrot wrote
>Hmm. Anyone else considdered what warfare between two O'Neils would
involve?<
something on a collision trajectory, too big for the meteoroid
sheilding to deal with. There are other ways, but once you've got
one, more don't make much difference.
I think more fighting will be within the constraints of *not* losing
excessive amounts of atmosphere or otherwise destroying the life
support systems of major colonies. I expect it will be a lot like
urban warfare and police work.
Destroying small spacecraft may be trivial or not, depending on the
technologies used.
# 7282 bylucioc@... on Nov. 26, 2005, 10:35 p.m.
Member since 2021-10-03
On 11/26/05, Dan Wylie-Sears wrote:
(...)
> Seems as though the nuclear option is pretty easy: put a lump of
> something on a collision trajectory, too big for the meteoroid
> sheilding to deal with. There are other ways, but once you've got
> one, more don't make much difference.
(...)
genocide for some reason or other. Even though, it may not be so easy
to get a nuke (or a kinetic weapon, also a viable alternative in
space) so close to the colony before it is detected and destroyed. (By
missiles or by death rays, which by the way may be not so difficult to
produce by simply concentrating sunlight over the target using an
array of mirrors.)
An enemy interested in *conquering* the habitat, though, will more
likely want to get some troop deploy vehicles in contact with the
outer hull, so that the troops can drill in and takeover the colony by
rather conventional urban warfare techniques. Humongous, country-sized
colonies, on the other hand, may require the deploy of tanks and war
planes...
# 7283 bydante_feditech@... on Nov. 27, 2005, 12:18 a.m.
Member since 2021-10-03
> From: Dan Wylie-Sears
> Seems as though the nuclear option is pretty easy: put a lump of
> something on a collision trajectory, too big for the meteoroid
> sheilding to deal with.
at 10kmps or more might simply punch through one side and out the other and
leave fairly clean holes. If all the energy is waster on blow-through
effects, then there might not be a lot of damage to the colony, or its
inhabitants. They'd loose all the air, it it would take several
minutes/hours for that to happen, which is enough time for people to get to
shelter or put on their survival suit. Which peopel woudl presumably carry
with them in wartime.
In fact a fairly sensible approach for a colony if it was under *severe* and
prolonged attack would be to depressurise the main volume to protect its
structure. (Preferably by putting the gas into storage.) Without the air
inside to violently superheat many WMDs are much less effective. The colony
is after all, a trillion ton block of reinforced concrete. ;)
> From: Lucio de Souza Coelho
> Of course this option is interesting only for people
> wanting to commit genocide for some reason or other.
Of course such a concept would be interest to hollywood too. It could
certianly prompt more interest than a space happy-families script like Space
Island One.
> Humongous, country-sized colonies, on the other
> hand, may require the deploy of tanks and war planes...
Imagine for example, two colony cylinders fighting each other over a truely
empty no-man's land...
John
How much free photo storage do you get? Store your holiday
# 7284 bydsw_s@... on Nov. 27, 2005, 6:55 a.m.
Member since 2021-10-03
"ANTIcarrot." wrote:
> The colony is after all, a trillion ton block of reinforced concrete
centrifugal weight with low curvature. Punch a hole in the Ringworld
and you get Fist of God Mountain; punch a hole in a rotating colony
built of real materials and the result may be catastrophic failure.
Will the colonies be engineered with the tolerances to survive a large
impact? I haven't thought it through, but I'm guessing that it will
be safer to not put all your eggs in one basket than to try to build a
basket capable of surviving someone's nuclear option.
# 7285 bydinmont2@... on Nov. 27, 2005, 2:12 p.m.
Member since 2021-10-03
--- In spacesettlers@yahoogroups.com, "Dan Wylie-Sears"
>
I suspect armed space ships will be a lot like modern day submarines
except their crews will operate in zero gravity.
> ANTIcarrot wrote
> >Hmm. Anyone else considdered what warfare between two O'Neils
would
> involve?<
>
> Seems as though the nuclear option is pretty easy: put a lump of
> something on a collision trajectory, too big for the meteoroid
> sheilding to deal with. There are other ways, but once you've got
> one, more don't make much difference.
>
> I think more fighting will be within the constraints of *not*
losing
# 7286 bydinmont2@... on Nov. 27, 2005, 2:22 p.m.
Member since 2021-10-03
There are always reasons for war. Struggle for resources competition.
England to grab colonials because they needed laborers. France didn't
see its colonies at the time as means for disposing of surplus
populations and its troublemakers. I suppose with colonies in space
growing rapidly, there will still be more resources than the means to
immiediately exploit them.
--- In spacesettlers@yahoogroups.com, Lucio de Souza Coelho
wrote:
>
> On 11/26/05, Dan Wylie-Sears wrote:
> (...)
> > Seems as though the nuclear option is pretty easy: put a lump of
> > something on a collision trajectory, too big for the meteoroid
> > sheilding to deal with. There are other ways, but once you've got
> > one, more don't make much difference.
> (...)
>
> Of course this option is interesting only for people wanting to
commit
> genocide for some reason or other. Even though, it may not be so
easy
> to get a nuke (or a kinetic weapon, also a viable alternative in
> space) so close to the colony before it is detected and destroyed.
(By
> missiles or by death rays, which by the way may be not so difficult
to
> produce by simply concentrating sunlight over the target using an
> array of mirrors.)
>
> An enemy interested in *conquering* the habitat, though, will more
> likely want to get some troop deploy vehicles in contact with the
> outer hull, so that the troops can drill in and takeover the colony
by
> rather conventional urban warfare techniques. Humongous, country-
sized
# 7287 bylevi1_ca@... on Nov. 27, 2005, 5:10 p.m.
Member since 2021-10-03
Perhaps there is less reason for war in space - the only reason I
could think of was location - there is no resource advantage -
everyone has to go somewhere to get basic materials - for expansion
you could build another colony - genocide would only get you
indignation of the entire system and perhaps your own demise - If you
don't like the neighbourhood then move the entire colony a few
thousand miles away- as for sending large asteroids ( large enough to
move comfortablely ) perhaps a recieving habitat would welcome them
with a fleet of scavange craft that would take them in pieces and use
the materials in the colony. It is possible that a blockade would work
really well though and you could force a colony to deplete its
resources in maintaining itself and thereby surrender to you.
# 7288 byhappygallimore@... on Nov. 27, 2005, 10:11 p.m.
Member since 2021-10-03
levi1_ca wrote:
Perhaps there is less reason for war in space - ... there is no resource advantage Why is there is less reason for war in space?
When you think about it, there would be the same logic of war. On earth wars could be political, religious or real estate claims, though a common reason was "resources". In space, there could be many resource conflicts. Just because space is a large doesn't mean there is practical access to needed resources.
Suppose there are some very critical, specialized components that one habitat cannot manufacture and another refuses to trade. This conflict could also lead to warfare.
In another hypothetical situation what if an automated mining camp gets hacked and the supplies go to another destination? (The desire to steal doesn't stop just because people leave earth.) The pirate habitat might have few tradable goods, limited manufacturing capability, or not been able to successfully operate its own resource bases.
If you have people, you have conflicts. In space there may be many resources, but we carbon and water-based organisms need a special environment just to live. In a harsh environment that requires adequate usable manufactured goods to keep our habitat viable. Raw resources may or may not be the contraint per se. Manufactured ones could be.
# 7289 bydinmont2@... on Nov. 28, 2005, 1:58 p.m.
Member since 2021-10-03
--- In spacesettlers@yahoogroups.com, Matt Gallimore
wrote:
>
> levi1_ca wrote:
> Perhaps there is less reason for war in space - ... there is no
resource advantage Why is there is less reason for war in space?
>
> If habitats become independent from earth, they must survive on
their own. That doesn't automatically lead to a happy brotherhood of
habitats.
>
> When you think about it, there would be the same logic of war. On
earth wars could be political, religious or real estate claims,
though a common reason was "resources". In space, there could be many
resource conflicts. Just because space is a large doesn't mean there
is practical access to needed resources.
>
> Suppose there are some very critical, specialized components that
one habitat cannot manufacture and another refuses to trade. This
conflict could also lead to warfare.
>
> In another hypothetical situation what if an automated mining
camp gets hacked and the supplies go to another destination? (The
desire to steal doesn't stop just because people leave earth.) The
pirate habitat might have few tradable goods, limited manufacturing
capability, or not been able to successfully operate its own resource
bases.
>
> If you have people, you have conflicts. In space there may be
many resources, but we carbon and water-based organisms need a
special environment just to live. In a harsh environment that
requires adequate usable manufactured goods to keep our habitat
viable. Raw resources may or may not be the contraint per se.
Manufactured ones could be.
>
for conflicts.
Another Scenerio is they might fight over a passing comet. Water is
not plentiful in space.
One scenerio not mentioned is Earth may decide to rule her colonies
much as the European governments tried to rule the new world. Seeing
them as revenue sources for their social spending programs. And some
might even decide to dictate to 'their' colonies how they are to
govern themselves.
# 7290 bylucioc@... on Nov. 28, 2005, 6:27 p.m.
Member since 2021-10-03
On 11/27/05, terrierkeeper wrote:
(...)
> Where ever mankind dwells there will always be war.
> I suspect armed space ships will be a lot like modern day submarines
> except their crews will operate in zero gravity.
I tend to agree here too. I would also think that those "submarines"
would not have passive shielding (though perhaps they would have some
form of light active shielding) for improving speed and maneuver
capacity. (That would expose the "sailors" to higher doses of space
radiation but somehow an increase of the risk of cancer 30 years in
the future seems pale in face of the risk of being nuked in a few
hours.)
I am thinking here about the "small fast ships" (or boats, whatever, I
never caught the subtlety between those two words in English), which I
would think certain to exist. However, would "heavy slow war
spaceships" also have their place? Gigantic ships with thick
shield-hulls able to withstand moderate nuking? Perhaps Battlestar
Galactica-like "aircraft carriers"? How much can we push into space
our analogies of warfare on Earth?
# 7291 byian.woollard@... on Dec. 30, 2005, 3:13 p.m.
Member since 2021-10-03
On 11/27/05, Dan Wylie-Sears wrote:
> ... under a vast amount of tension so as to support its own
> centrifugal weight with low curvature.
1 Earth normal atmospheric loading is 10 tonnes per square meter. The
weight of one square meter of floor material at 1 earth normal gravity
is *much* less; well under a tonne.
> Punch a hole in the Ringworld
> and you get Fist of God Mountain; punch a hole in a rotating colony
> built of real materials and the result may be catastrophic failure.
Maybe, maybe not. My gut feel is not.
You've just reduced the main load- atmospheric loading at the breach
point, so it might well survive in fact.
Also, the volume of a habitat is vast. It takes a very big hole to
depressurise one in less than days.
I mean, an aeroplane at 30 thousand feet can lose a window, and still
reach 30 thousand feet in a few minutes without everyone suffocating.
Concorde had smaller windows because it was higher and took longer to
come down.
You need to think how much more volume a habitat has than an aeroplane.
O'Neill said it would take *days* to depressurise enough that you
would have to evacuate from a 1kg lump meteorite hole for example.
-Ian Woollard
Identity cards, cameras on every corner, long term detention without
trial, electronic tapping and reading of email/phone calls, speed
cameras that increase the death rate, extradition for torture - It's
all double plus good, Big Brother Blair and Uncle Bush are my friend!
# 7292 bydsw_s@... on Jan. 10, 2006, 11:01 p.m.
Member since 2021-10-03
> You've just reduced the main load- atmospheric loading at the
> breach point, so it might well survive in fact.
structure. It's simpler to visualize for a cylinder: the stress is
pure tension, all in the circumference direction, and two strips
along opposite sides have to keep the two halves from going their
separate ways: they have to bear the component parallel to their
tangential direction, of centrifugal weight plus atmospheric
pressure of the two halves. The outward force acting at that point
is perpendicular: varying the amount of mass or air pressure there
has no effect on the tension there, and maximal effect on the
tension 90 degrees away.
> Identity cards, cameras on every corner, long term detention
> without trial,
Hey, don't forget without access to a lawyer and without so much as
a warrant from the courts.
>speed cameras that increase the death rate<
How does that work?
--- In spacesettlers@yahoogroups.com, Ian Woollard
wrote:
>
> On 11/27/05, Dan Wylie-Sears wrote:
> > ... under a vast amount of tension so as to support its own
> > centrifugal weight with low curvature.
>
> Nope. Atmospheric loading is much less.
>
> 1 Earth normal atmospheric loading is 10 tonnes per square meter.
The
> weight of one square meter of floor material at 1 earth normal
gravity
> is *much* less; well under a tonne.
>
> > Punch a hole in the Ringworld
> > and you get Fist of God Mountain; punch a hole in a rotating
colony
> > built of real materials and the result may be catastrophic
failure.
>
> Maybe, maybe not. My gut feel is not.
>
> You've just reduced the main load- atmospheric loading at the
breach
> point, so it might well survive in fact.
>
> Also, the volume of a habitat is vast. It takes a very big hole to
> depressurise one in less than days.
>
> I mean, an aeroplane at 30 thousand feet can lose a window, and
still
> reach 30 thousand feet in a few minutes without everyone
suffocating.
> Concorde had smaller windows because it was higher and took longer
to
> come down.
>
> You need to think how much more volume a habitat has than an
aeroplane.
>
> O'Neill said it would take *days* to depressurise enough that you
> would have to evacuate from a 1kg lump meteorite hole for example.
>
> --
> -Ian Woollard
>
> Identity cards, cameras on every corner, long term detention
without
> trial, electronic tapping and reading of email/phone calls, speed
> cameras that increase the death rate, extradition for torture -
It's
> all double plus good, Big Brother Blair and Uncle Bush are my
friend!
# 7293 byian.woollard@... on Jan. 11, 2006, 12:05 a.m.
Member since 2021-10-03
On 1/10/06, Dan Wylie-Sears wrote:
> > You've just reduced the main load- atmospheric loading at the
> > breach point, so it might well survive in fact.
>
> The load on a sphere or cylinder is from the whole rest of the
> structure.
structure, so punching a few smallish holes in the cylinder makes
little difference.
> It's simpler to visualize for a cylinder: the stress is
> pure tension, all in the circumference direction,
Actually there's also longitudinal stress, 50% of the circumferental
stress, which is caused by air pressure on the end caps.
> and two strips
> along opposite sides have to keep the two halves from going their
> separate ways: they have to bear the component parallel to their
> tangential direction, of centrifugal weight plus atmospheric
> pressure of the two halves. The outward force acting at that point
> is perpendicular: varying the amount of mass or air pressure there
> has no effect on the tension there, and maximal effect on the
> tension 90 degrees away.
Well, you've reduced the load on the structure by more than the size
of the hole.
I guess punching a hole in the wall has a stress concentrating effect
around it; I vaguely recall it's about a factor of 3 for a circular
hole. It's somewhat higher for a crack.
> >speed cameras that increase the death rate<
>
> How does that work?
Death rate goes up when they install cameras. Probably everyone
stomping on their brakes on straight roads and getting rammed from
behind and stuff.
-Ian Woollard
Identity cards, cameras on every corner, long term detention without
trial, electronic tapping and reading of email/phone calls, speed
cameras that increase the death rate, extradition for torture - It's
all double plus good, Big Brother Blair and Uncle Bush are my friend!
# 7294 bydsw_s@... on Jan. 12, 2006, 3:20 p.m.
Member since 2021-10-03
> Actually there's also longitudinal stress, 50% of the
circumferental
> stress, which is caused by air pressure on the end caps.
something more complicated, because the circumferential stress
depends on the g's whereas the longitudinal stress depends only on
the pressure.
> Well, you've reduced the load on the structure by more than the
size
> of the hole.
I still don't get it. How do those quantities even have the same
dimensions?
--- In spacesettlers@yahoogroups.com, Ian Woollard
wrote:
>
> On 1/10/06, Dan Wylie-Sears wrote:
> > > You've just reduced the main load- atmospheric loading at the
> > > breach point, so it might well survive in fact.
> >
> > The load on a sphere or cylinder is from the whole rest of the
> > structure.
>
> True, but you have a safety factor of maybe 2-4 on the whole
> structure, so punching a few smallish holes in the cylinder makes
> little difference.
>
> > It's simpler to visualize for a cylinder: the stress is
> > pure tension, all in the circumference direction,
>
> Actually there's also longitudinal stress, 50% of the
circumferental
> stress, which is caused by air pressure on the end caps.
>
> > and two strips
> > along opposite sides have to keep the two halves from going their
> > separate ways: they have to bear the component parallel to their
> > tangential direction, of centrifugal weight plus atmospheric
> > pressure of the two halves. The outward force acting at that
point
> > is perpendicular: varying the amount of mass or air pressure
there
> > has no effect on the tension there, and maximal effect on the
> > tension 90 degrees away.
>
> Well, you've reduced the load on the structure by more than the
size
> of the hole.
>
> I guess punching a hole in the wall has a stress concentrating
effect
> around it; I vaguely recall it's about a factor of 3 for a circular
> hole. It's somewhat higher for a crack.
>
> > >speed cameras that increase the death rate<
> >
> > How does that work?
>
> Death rate goes up when they install cameras. Probably everyone
> stomping on their brakes on straight roads and getting rammed from
> behind and stuff.
>
> --
> -Ian Woollard
>
> Identity cards, cameras on every corner, long term detention
without
> trial, electronic tapping and reading of email/phone calls, speed
> cameras that increase the death rate, extradition for torture -
It's
> all double plus good, Big Brother Blair and Uncle Bush are my
friend!
# 7295 byian.woollard@... on Jan. 12, 2006, 5:52 p.m.
Member since 2021-10-03
On 1/12/06, Dan Wylie-Sears wrote:
> > Actually there's also longitudinal stress, 50% of the
> circumferental
> > stress, which is caused by air pressure on the end caps.
>
> How does it come out so simple?
It's easy to work out how much metal you need to stop a pressure
vessel exploding. You cut it with imaginary planes and work out how
much force (=pressure*gasArea) there is trying to blow the two halves
apart and then you make sure you have enough metal to stop it doing
that (tensile strength*metalArea/safetyFactor) in that plane.
In this case, the amount of metal needed to stop a cylinder exploding
lengthwise is half that needed to stop it bursting circumferentially.
> It seems as though it has to be
> something more complicated, because the circumferential stress
> depends on the g's whereas the longitudinal stress depends only on
> the pressure.
To a first order approximation the rotation can be neglected. The
atmospheric pressure is 5-10 tonnes, but the weight of the floor is
only about 10-20% of that.
> > Well, you've reduced the load on the structure by more than the
> size
> > of the hole.
>
> I still don't get it. How do those quantities even have the same
> dimensions?
You're removed the hole, which means the strength has gone down, but
you've also removed the load where the hole used to be. Also the air
pressure around the hole is lower too, so you've reduced the load
surrounding the hole as well.
-Ian Woollard
Identity cards, cameras on every corner, long term detention without
trial, electronic tapping and reading of email/phone calls, speed
cameras that increase the death rate, extradition for torture - It's
all double plus good, Big Brother Blair and Uncle Bush are my friend!
# 7296 bydsw_s@... on Jan. 13, 2006, 4:37 a.m.
Member since 2021-10-03
Once the weight is assumed to be negligible, I have no problem with
that calculation. It's just that I expected there to be a
significant amount of mass there, without doing an calculation.
will rotate? How are you assuming the interior structure will be
supported, or are you just assuming it has negligible weight?
I also had in the back of my mind, although it's not directly
relevant to the simple cylinder, that we wouldn't want to pressurize
the whole interior because we're likely to have limited use for low-
g pressurized volume where no one can live much of the time without
bone loss. If the colony is large enough that the low-g interior
volume is more than you want to pressurize, but not so large that
you have a whole sky-full of atmosphere overhead, then part of the
pressure becomes tensile stress on interior components connecting
the inner cylinder to the outer. Odd to imagine your buildings
hanging from the ceiling supported by air pressure, but I suppose a
colony could be designed that way.
Btw, I note that your formula has the structural material being
metal, which I don't assume it would.
--- In spacesettlers@yahoogroups.com, Ian Woollard
wrote:
>
> On 1/12/06, Dan Wylie-Sears wrote:
> > > Actually there's also longitudinal stress, 50% of the
> > circumferental
> > > stress, which is caused by air pressure on the end caps.
> >
> > How does it come out so simple?
>
> I don't know of any deep reason for it, but I know how to prove it.
>
> It's easy to work out how much metal you need to stop a pressure
> vessel exploding. You cut it with imaginary planes and work out how
> much force (=pressure*gasArea) there is trying to blow the two
halves
> apart and then you make sure you have enough metal to stop it doing
> that (tensile strength*metalArea/safetyFactor) in that plane.
>
> In this case, the amount of metal needed to stop a cylinder
exploding
> lengthwise is half that needed to stop it bursting
circumferentially.
>
> > It seems as though it has to be
> > something more complicated, because the circumferential stress
> > depends on the g's whereas the longitudinal stress depends only
on
> > the pressure.
>
> To a first order approximation the rotation can be neglected. The
> atmospheric pressure is 5-10 tonnes, but the weight of the floor is
> only about 10-20% of that.
>
> > > Well, you've reduced the load on the structure by more than the
> > size
> > > of the hole.
> >
> > I still don't get it. How do those quantities even have the same
> > dimensions?
>
> You're removed the hole, which means the strength has gone down,
but
> you've also removed the load where the hole used to be. Also the
air
> pressure around the hole is lower too, so you've reduced the load
> surrounding the hole as well.
>
> --
> -Ian Woollard
>
> Identity cards, cameras on every corner, long term detention
without
> trial, electronic tapping and reading of email/phone calls, speed
> cameras that increase the death rate, extradition for torture -
It's
> all double plus good, Big Brother Blair and Uncle Bush are my
friend!
# 7297 byhappygallimore@... on Jan. 13, 2006, 5:15 a.m.
Member since 2021-10-03
Without going into too much math, could someone explain why the circumferential stress would be 2x the longitudinal tensile stress?
Thus my question if someone knows why, in laymen's terms, why the radial loading is greater than the tensile longitudinal loading?
From: Ian Woollard
To: spacesettlers@yahoogroups.com
Sent: Thursday, January 12, 2006 12:52:31 PM
Subject: [spacesettlers] Re: War in space
On 1/12/06, Dan Wylie-Sears wrote:
> > Actually there's also longitudinal stress, 50% of the
> circumferental
> > stress, which is caused by air pressure on the end caps.
>
> How does it come out so simple?
I don't know of any deep reason for it, but I know how to prove it.
It's easy to work out how much metal you need to stop a pressure
vessel exploding. You cut it with imaginary planes and work out how
much force (=pressure*gasArea) there is trying to blow the two halves
apart and then you make sure you have enough metal to stop it doing
that (tensile strength*metalArea/safetyFactor) in that plane.
In this case, the amount of metal needed to stop a cylinder exploding
lengthwise is half that needed to stop it bursting circumferentially.
> It seems as though it has to be
> something more complicated, because the circumferential stress
> depends on the g's whereas the longitudinal stress depends only on
> the pressure.
To a first order approximation the rotation can be neglected. The
atmospheric pressure is 5-10 tonnes, but the weight of the floor is
only about 10-20% of that.
> > Well, you've reduced the load on the structure by more than the
> size
> > of the hole.
>
> I still don't get it. How do those quantities even have the same
> dimensions?
You're removed the hole, which means the strength has gone down, but
you've also removed the load where the hole used to be. Also the air
pressure around the hole is lower too, so you've reduced the load
surrounding the hole as well.
-Ian Woollard
Identity cards, cameras on every corner, long term detention without
trial, electronic tapping and reading of email/phone calls, speed
cameras that increase the death rate, extradition for torture - It's
all double plus good, Big Brother Blair and Uncle Bush are my friend!
# 7298 bydsw_s@... on Jan. 13, 2006, 5:32 p.m.
Member since 2021-10-03
We haven't discussed anything that requires considering moments at
all, nor have we addressed the stresses at different locations. We've
only been talking about the stress at a point on the surface of the
cylinder, and comparing the components in different directions.
force is all borne by the sides. There are no complicated torques and
shear stresses, just tension around the outside to resist the radial
force and tension along the length to resist the force pushing the end
caps apart. Figuring out the stresses on the end caps would require
the stuff you're thinking about, but we hadn't been doing that.
The layman's-terms reason why the force is greater in the longitudinal
direction is that there's no curvature in the longitudinal direction.
To see the connection between curvature and stress, it's simpler with
spheres. Think of a big balloon and a little balloon with the same
pressure, and draw a circle around each: each needs to be strong
enough to keep the two halves together, with the material around the
circle being strong enough for the pressure pushing them apart. The
pressure is proportionl to area so increases as the square of radius;
the amount of material is proportional to the circumference of the
circle, so increases linearly with radius. So the big balloon has to
be stronger. Bigger means less curvature.
--- In spacesettlers@yahoogroups.com, Matt Gallimore
wrote:
>
> Without going into too much math, could someone explain why the
circumferential stress would be 2x the longitudinal tensile stress?
>
> At the moment I was just thinking about the cylinder length. At the
L/2 you would have maximum moment force loading the two ends. The
ends have tremendous tensile loading, but so would the cylinder at mid-
length. The image in my mind was that you might need some cables to
give structural support midway. However, this is one of those things
that I am certain it has been considered by many before from the 70s
forward.
>
> Thus my question if someone knows why, in laymen's terms, why the
radial loading is greater than the tensile longitudinal loading?