Author Topic: Envisioning Amazing Martian Habitats  (Read 279031 times)

Offline Lampyridae

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Re: Envisioning Amazing Martian Habitats
« Reply #1540 on: 12/05/2018 01:59 PM »
........Which is why SpaceX is heading underground: the radiation issue is solved.

Also: when you go underground you don't make structures, you make spaces. The structures are already there. In abundance. They're called bedrock.

Sure, living underground can be a bit oppressive. However, it won't be the first time humanity starts settling a planet by living in caves.

As someone who spends their time looking at fractured borehole wall rock, I can tell you that it is not the panacea people think it is. Studies of lunar and Martian base construction mention it, then toss it aside because of the problems.

You have to physically cut (heavy equipment) and remove it (heavy equipment), whilst keeping the support structure intact through pillars or rockbolts and shotcrete, and even then it crumbles and collapses. Earthmoving equipment depends on its weight for purchase. On Mars, these things are reduced. Your tunnel boring machine could start turning on its own axis if it's not securely anchored.

Typical depths to competent bedrock on Earth are on the order of 20-30m. On Mars, it's a complete unknown.

If for some reason you are in a section that is cut off in an emergency, someone has to actively tunnel to get to you. A structural failure would mean tonnes of rock collapsing on you. If you are digging the tunnel, you can lose your tunnelling machine to structural failure. Or worse, you could discover that competent bedrock is absolutely nonexistent down to 50m.

Assuming you overcome all these challenges, and seal the tunnels with sintered concrete / vitrification, build in escape stairways, you then discover that because you have landed in an area with permafrost for propellant and water, the waste heat from your underground habs has started to melt it...

*"You" being the hypothetical Martian settlers

Now there are ways to build underground on Mars, but hiring The Boring Company is not going to be the solution. Lava tubes are there, vitrified and easy to seal. Cutting into a mesa like in Red Mars which was mentioned upthread is another valid idea, although subject to the questions of rock competency I would ask.
« Last Edit: 12/05/2018 02:05 PM by Lampyridae »
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Offline RonM

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Re: Envisioning Amazing Martian Habitats
« Reply #1541 on: 12/05/2018 06:16 PM »
According to astronauts who've done space-walks, you feel pretty genuinely "out there", even though you're in what is effectively a mini-spaceship and are merely looking out a window.

When I go outside I don't really feel like I'm "out there" until I put my glasses on. Without those two "windows" everything looks fuzzy.

Think of an EVA suit as heavy clothing and a helmet, just like what you should wear riding a motorcycle.

Offline Paul451

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Re: Envisioning Amazing Martian Habitats
« Reply #1542 on: 12/06/2018 01:49 AM »
Which is why SpaceX is heading underground: the radiation issue is solved. Also: when you go underground you don't make structures, you make spaces. The structures are already there. In abundance. They're called bedrock.

Bedrock isn't required. The requirements for radiation, even assuming the worst numbers and the least tolerance for risk, require only a few metres of regolith.

Just as you can pile rubble over your surface modules, you can cut down and cover with lose material. Or, just as you can sinter regolith blocks for external structural elements and just add the internal pressure liner, you can cut and sinter a buried structure into which you add the pressure vessels proper.

(To answer the obvious question: if you can cover surface modules, why add the hassle of also excavating down? You have to dig up the regolith to cover the habs. So use the hole you dug. For any given volume of covering, putting the module in the hole reduces the amount you need to dig. Although you might end up with a sort of half-buried, half-covered structure. But I'm not a purist. Whatever works, works.)

You don't need bedrock. Indeed, you might actively avoid it until your capabilities have improved. And even then, only dig into bedrock because the size of the structures exceeds the depth of the regolith.

(The exception will be if you have to dig water out of buried aquifers. Then you have to know how to dig down, how to support your work areas, and since you have that excavated volume available...)

[edit: split out the other part of my reply into a separate post]
« Last Edit: 12/06/2018 01:51 AM by Paul451 »

Offline Paul451

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Re: Envisioning Amazing Martian Habitats
« Reply #1543 on: 12/06/2018 01:50 AM »
Earthmoving equipment depends on its weight for purchase. On Mars, these things are reduced.

As I understand it, some diggers (like TBMs) don't rely on weight, but push against their previous anchor points. I suspect something similar will need to be done for all earthmoving equipment. Deployable anchors that dig in behind any vehicle when it needs to push forward.

This would be required for all surface work, even just a grader, so it's a general problem, not just for underground work.

you then discover that because you have landed in an area with permafrost for propellant and water, the waste heat from your underground habs has started to melt it...

To be fair, you aren't going to "discover" this after-the-fact. Civil engineering isn't new. Assaying rock, making stable underground structures, understanding water movement, etc, is all stuff we do already. The maths needs to get tweaked for Mars (less gravity, pressure difference), but the basis for the maths is the same.

Cutting into a mesa like in Red Mars which was mentioned upthread is another valid idea, although subject to the questions of rock competency I would ask.

Cutting into a mesa is cutting into bedrock.

Lava tubes are there, vitrified and easy to seal.

The latter is debatable. We don't know how structurally sound any tube would be, how permeable/airtight, how clear. We'd have to do the same engineering analysis as with any underground work. (The advantage is that it is, nonetheless, pre-dug.)

As I've mentioned many times, my favourite part of lava tubes is that anything underground will have a temperature that is the average of the surface temperature (heat-pulses mush together the deeper you go). For most places on Mars, even at the equator, lava tubes would be below freezing. Hence water vapour that heats up on the surface will freeze out in the tubes. I suspect that a short way inside from any skylight or breach will be a solid plug of water ice. (Maybe CO₂ as well, depending on the temp.)

Radiation shielding, huge excavated volumes, water in a nice solid filtered form. What's not to love.

Offline JasonAW3

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Re: Envisioning Amazing Martian Habitats
« Reply #1544 on: 12/06/2018 02:00 AM »
A thin, transparent  layer, like on helmets? Only from alpha (helium nuclei) and low energy beta (electrons). Higher  energy beta hitting gold will create x-rays via bremstrahlung, and hard x-rays will pass through a transparent coating- or worse, scatter. 

Lead or barium/lead  glass is better, and ALON may be acceptable for mild environments (impact resistant too).

Eh, I still like the aquaponics window idea...

      The image of exotic, or even food fish swimming against a Martian horizon and landscape gives me a bit of a kick!
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Offline MickQ

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Re: Envisioning Amazing Martian Habitats
« Reply #1545 on: 12/06/2018 10:40 AM »
Personally, I think both would/should be included. Different people will have different ideas of what "Open Space" means.  A couple of 2 or 3 metre diameter dome shaped structures with 6 or 8 windows around the circumference would provide ample viewing of the outside while a large room full of plants, an indoor garden, will also have a therapeutic effect at other times.

Offline Oersted

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Re: Envisioning Amazing Martian Habitats
« Reply #1546 on: 12/06/2018 03:15 PM »
........Which is why SpaceX is heading underground: the radiation issue is solved.

Also: when you go underground you don't make structures, you make spaces. The structures are already there. In abundance. They're called bedrock.

Sure, living underground can be a bit oppressive. However, it won't be the first time humanity starts settling a planet by living in caves.

As someone who spends their time looking at fractured borehole wall rock, I can tell you that it is not the panacea people think it is. Studies of lunar and Martian base construction mention it, then toss it aside because of the problems.

You have to physically cut (heavy equipment) and remove it (heavy equipment), whilst keeping the support structure intact through pillars or rockbolts and shotcrete, and even then it crumbles and collapses. Earthmoving equipment depends on its weight for purchase. On Mars, these things are reduced. Your tunnel boring machine could start turning on its own axis if it's not securely anchored.

Typical depths to competent bedrock on Earth are on the order of 20-30m. On Mars, it's a complete unknown.

If for some reason you are in a section that is cut off in an emergency, someone has to actively tunnel to get to you. A structural failure would mean tonnes of rock collapsing on you. If you are digging the tunnel, you can lose your tunnelling machine to structural failure. Or worse, you could discover that competent bedrock is absolutely nonexistent down to 50m.

Assuming you overcome all these challenges, and seal the tunnels with sintered concrete / vitrification, build in escape stairways, you then discover that because you have landed in an area with permafrost for propellant and water, the waste heat from your underground habs has started to melt it...

*"You" being the hypothetical Martian settlers

Now there are ways to build underground on Mars, but hiring The Boring Company is not going to be the solution. Lava tubes are there, vitrified and easy to seal. Cutting into a mesa like in Red Mars which was mentioned upthread is another valid idea, although subject to the questions of rock competency I would ask.

Thanks for your great contribution in response to my posting!

For sure tunnelling in bedrock is fraught with difficulties. We agree on that.

However, the relevant question is: how big are the difficulties compared to the difficulties of other methods?

This is where I see several advantages of tunnelling.

- The major limitation of working on Mars is the mass budget. Energy is there in abundance (solar or small nuclear reactor), but there is no getting around that you are severely limited in how much material you can land on Mars.

In the initial stage it is obvious that the habs will just be the spaceships. However, when you move beyond that stage how will you expand? With prefab habs? Building habs on the surface? Both methods are mass prohibitive. Even if you pile regolith on surface structures you still need to bring those structures in the first place.

This is why the holy grail for expanding the interior volume on Mars involves going underground. And it needs to be in a structurally self-sustaining and self-pressurized interior volume.

I hear you when you say that lots of caves and tunnels on Earth are not structurally self-sustaining; However, there ARE also very many self-sustaining underground habitats. The geology of Earth allows them in a multitude of places and I have not read that Mars should be any different; If anything Mars is more geologically stable than Earth (less erosion, no tectonics, etc).

It will take a thorough reconnaissance campaign to find just the right spot, a spot which contains stable solid bedrock near a water resource, preferably allowing a horizontal entrance from the surface. As they say: "location is everything."

That's also why lava tubes, enticing though they are, probably won't do, since it would require a minor miracle to find one in just the right place. Another problem with lava tubes is sealing the entrance, which may be of a huge diameter. If you do your own tunnelling it should prove relatively straightforward to plug the entrance.

When tunnelling you only need machinery and energy (and the energy is there). The rest, i.e. the MASS LIMITED raw materials, are already there.

It is pretty clear to me that it is the reason why Musk is actively exploring exponential improvements in tunneling technology. He has taken a first principles approach to the settling of Mars and come to the same conclusion as the one I (and many others) are proposing. Yes, tunnelling on Mars will be devilishly difficult, but it is the best way to attempt limitless expansion (in theory) of habitable volume on a very mass-limited budget.   

Offline lamontagne

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Re: Envisioning Amazing Martian Habitats
« Reply #1547 on: 12/06/2018 03:57 PM »
I see this thread has picked up again!

I will be working on a design for the Mars Society Colony prize, and I guess I might as well post my stuff here, since I am hoping to make an amazing design!  And I will be recycling some of my earlier work.

The core element in the design is a tunnel system.  I would use  Roadheader(s) to make the tunnel in what I hope would be fairly soft stone, clay/sandstone  rocky mixture, in one of the partially erosion filled craters. 
Then build structural pressure resistant linings inside the tunnels.  The linings would be offset from the walls, so most thermal transfer would be by radiation, as the space between the walls will be at Martian atmospheric pressure.
The liners would be made from Compressed Earth Bricks (CEB), made on the spot.  I'm still looking into if I need to add some kind of cement for waterproofing and air tightness.  But I'm planning for some continuous leakage.
Te actual strength of the liners would come from external hoops of carbon fiber wires, post tensionned, eventually replaced by locally produced steel.  Longitudinal strength would be from rods set between the blocks.

I'm looking at intersections, and will try to figure out a reasonable way of making them, as I want a complex multi tube system for a richer environment.

The base will be insulated by the vacuum and low emissivity coatings, so it will overheat and require active cooling, probably using air currents, but perhaps some circulation water as well.

I'll include a number of surface domes for a more varied environment.

I'm open to suggestions and ideas, as I've got till the end of March to finish the thing.
The blocks are 400mm x 400mm x 1000mm..  That might be too big for realistic CEB, but there are some failry large elements visible on the net.



« Last Edit: 12/06/2018 04:00 PM by lamontagne »

Online Slarty1080

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Re: Envisioning Amazing Martian Habitats
« Reply #1548 on: 12/06/2018 06:36 PM »
I see this thread has picked up again!

I will be working on a design for the Mars Society Colony prize, and I guess I might as well post my stuff here, since I am hoping to make an amazing design!  And I will be recycling some of my earlier work.

The core element in the design is a tunnel system.  I would use  Roadheader(s) to make the tunnel in what I hope would be fairly soft stone, clay/sandstone  rocky mixture, in one of the partially erosion filled craters. 
Then build structural pressure resistant linings inside the tunnels.  The linings would be offset from the walls, so most thermal transfer would be by radiation, as the space between the walls will be at Martian atmospheric pressure.
The liners would be made from Compressed Earth Bricks (CEB), made on the spot.  I'm still looking into if I need to add some kind of cement for waterproofing and air tightness.  But I'm planning for some continuous leakage.
Te actual strength of the liners would come from external hoops of carbon fiber wires, post tensionned, eventually replaced by locally produced steel.  Longitudinal strength would be from rods set between the blocks.

I'm looking at intersections, and will try to figure out a reasonable way of making them, as I want a complex multi tube system for a richer environment.

The base will be insulated by the vacuum and low emissivity coatings, so it will overheat and require active cooling, probably using air currents, but perhaps some circulation water as well.

I'll include a number of surface domes for a more varied environment.

I'm open to suggestions and ideas, as I've got till the end of March to finish the thing.
The blocks are 400mm x 400mm x 1000mm..  That might be too big for realistic CEB, but there are some failry large elements visible on the net.
Sounds like an interesting project. Perhaps the tunnelling approach and the lava tube approach are not mutually exclusive. If a suitable lava tube can be found with a shallow angle that is accessible and goes deep enough why not use the lava tube to access deeper layers of rock directly without having to dig vertically first? Just dig into the wall of the lava tube and keep going. Could also build some habitat elements in the lava tube and cover them with spoil from the tunnelling.
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Offline Oersted

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Re: Envisioning Amazing Martian Habitats
« Reply #1549 on: 12/06/2018 07:15 PM »
Good point. Only question: will the lava tube be in the right spot?

Offline lamontagne

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Re: Envisioning Amazing Martian Habitats
« Reply #1550 on: 12/06/2018 07:20 PM »
I see this thread has picked up again!

I will be working on a design for the Mars Society Colony prize, and I guess I might as well post my stuff here, since I am hoping to make an amazing design!  And I will be recycling some of my earlier work.

The core element in the design is a tunnel system.  I would use  Roadheader(s) to make the tunnel in what I hope would be fairly soft stone, clay/sandstone  rocky mixture, in one of the partially erosion filled craters. 
Then build structural pressure resistant linings inside the tunnels.  The linings would be offset from the walls, so most thermal transfer would be by radiation, as the space between the walls will be at Martian atmospheric pressure.
The liners would be made from Compressed Earth Bricks (CEB), made on the spot.  I'm still looking into if I need to add some kind of cement for waterproofing and air tightness.  But I'm planning for some continuous leakage.
Te actual strength of the liners would come from external hoops of carbon fiber wires, post tensionned, eventually replaced by locally produced steel.  Longitudinal strength would be from rods set between the blocks.

I'm looking at intersections, and will try to figure out a reasonable way of making them, as I want a complex multi tube system for a richer environment.

The base will be insulated by the vacuum and low emissivity coatings, so it will overheat and require active cooling, probably using air currents, but perhaps some circulation water as well.

I'll include a number of surface domes for a more varied environment.

I'm open to suggestions and ideas, as I've got till the end of March to finish the thing.
The blocks are 400mm x 400mm x 1000mm..  That might be too big for realistic CEB, but there are some failry large elements visible on the net.
Sounds like an interesting project. Perhaps the tunnelling approach and the lava tube approach are not mutually exclusive. If a suitable lava tube can be found with a shallow angle that is accessible and goes deep enough why not use the lava tube to access deeper layers of rock directly without having to dig vertically first? Just dig into the wall of the lava tube and keep going. Could also build some habitat elements in the lava tube and cover them with spoil from the tunnelling.
You can put a pressurized habitat in a lava tube.  that is basically what National Geographic proposed in a recent issue.  You could eventually build the habitats using exclusively local materials.
As lavatubes are, as far as I know, essentially basaltic, we could probably develop a local industry using basalt fibers in a organic or metallic matrix, with the main bulk of the habitats sintered basalt or even steel, if there is iron nearby.
However, for the purpose of the colony design, I will presume the colonists did not identify a handy tube with large amounts of water nearby, but have to create the entire habitat from scratch.  the difference will essentially be the power required for digging (about 1-2 kWh per m3 in my rule of thumb for the moment) and hauling the tunnel material, so one could argue they are essentially the same project, with the artificial tunnel one being more conservative.

Offline lamontagne

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Re: Envisioning Amazing Martian Habitats
« Reply #1551 on: 12/06/2018 07:28 PM »
Good point. Only question: will the lava tube be in the right spot?
I'm guessing it will not be.  Otherwise, I think both solutions are fairly similar, the main cost difference being the rate of use of the digging equipment, thousands of hours for tunnels vs hundreds for tubes.  I expect sintered basalt blocks are more expensive the CEB blocs, but that hardly offsets the digging costs.

Offline Paul451

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Re: Envisioning Amazing Martian Habitats
« Reply #1552 on: 12/07/2018 12:23 AM »
Te actual strength of the liners would come from external hoops of carbon fiber wires, post tensionned, eventually replaced by locally produced steel. Longitudinal strength would be from rods set between the blocks.

Why not extruded basalt? (And not just basalt fibre in a matrix. Extruded basalt rods and mesh are already used in building to reinforce concrete. Well, technically the concrete is the matrix, but you get what I mean. Half inch rods are not "fibre".)

that is basically what National Geographic proposed in a recent issue.

And that god-awful series they made.



how will you expand? With prefab habs? Building habs on the surface? Both methods are mass prohibitive. Even if you pile regolith on surface structures you still need to bring those structures in the first place.

If you can't build an airtight shell, IMO you're not capable of settling Mars.

A basic airtight shell is the equivalent of building a lean-to in a forest. It's the absolute technological minimum cost of entry if you expect to do more than short exploration-and-return.

When tunnelling you only need machinery and energy (and the energy is there). The rest, i.e. the MASS LIMITED raw materials, are already there.

Plus the consumables of the machines.

If you want to build an airtight chamber in raw rock, the walls have to be non-permeable, that rules out soft rock, if you want it to self-support over fairly large areas, that also rules out soft-rock. So you're looking at hard granites. You are going to be consuming a surprising amount of parts to keep the, for example, road-headers running. If that mass is greater than the mass of a shell equivalent to that volume, you haven't saved anything.

Likewise, is the mass of digging equipment necessary for cutting underground structures higher than the mass of equipment for making ISRU airtight shells?

(This argument holds for my suggestion of cut'n'cover. You do need machines to work regolith anyway, but if you bury every hab, the rate of wear on those machines is much higher than if you're just levelling roads and landing-pads.)

It is pretty clear to me that it is the reason why Musk is actively exploring exponential improvements in tunneling technology.

Perhaps, but it's worth noting that the savings he suggests came from reducing the diameter of the tunnel, by using electric "skateboards" instead of having to have full lanes for running cars and full height for trucks. Halve the diameter, quarter the volume dug. He hasn't actually changed tunnel boring the way he has launch costs, distributed power storage, and electric cars.

Online matthewkantar

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Re: Envisioning Amazing Martian Habitats
« Reply #1553 on: 12/07/2018 12:59 AM »
If an arch of loose stone can be built, a dome can be built. Pile an arbitrary tonnage of stone on top of the dome, don't worry about small gaps.  Insert a one piece membrane with an integrated airlock and you have a pretty good shelter. No tools needed, just gather rocks. Hand carryable rocks will be 2.5 times larger than they are on earth.

Offline Lampyridae

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Re: Envisioning Amazing Martian Habitats
« Reply #1554 on: 12/07/2018 07:05 AM »
Good point. Only question: will the lava tube be in the right spot?

This is a good question, one which I hope to answer in MSc thesis (still at the proposal stage). But I can tell you that most lava tubes are in the Tharsis Montes region, which, since it lacks sedimentary runoff, doesn't have a lot in the way of promising surface minerals: hydrates, aluminosillicates etc. They're also at higher altitudes and latitudes. But the ones near Noctis Landing, near the equator and feeding into Valles Marineris, look like promising candidates. I think that's where the Mars TV series is located, too.
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Offline Lampyridae

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Re: Envisioning Amazing Martian Habitats
« Reply #1555 on: 12/07/2018 08:28 AM »
Earthmoving equipment depends on its weight for purchase. On Mars, these things are reduced.

As I understand it, some diggers (like TBMs) don't rely on weight, but push against their previous anchor points. I suspect something similar will need to be done for all earthmoving equipment. Deployable anchors that dig in behind any vehicle when it needs to push forward.

This would be required for all surface work, even just a grader, so it's a general problem, not just for underground work.

The gripper force is dictated by a number of things, including the weight of the TBM. But for the concrete-laying types (ie the ones that don't drill through hard, competent rock) they also push against the edges of the concrete that has been laid. Gravity also affects a TBM as the rock chips fall through gutters in the cutting disc into a hopper and out a chute at the back. Alternatively, they go into a slurry and get pumped out back.

Speaking of pumping, TBMs convert all of their input energy into heat (hundreds of kilowatts even for a small borer, a megawatt for one large enought to dig comfortably sized tunnels). About half of that goes into the broken rock, a quarter or so gets carried out by the slurry (if you have it). The rest of it, on Mars, must be handled by coolant cables. Those must go out to the top to a radiator array.

Quote
you then discover that because you have landed in an area with permafrost for propellant and water, the waste heat from your underground habs has started to melt it...

To be fair, you aren't going to "discover" this after-the-fact. Civil engineering isn't new. Assaying rock, making stable underground structures, understanding water movement, etc, is all stuff we do already. The maths needs to get tweaked for Mars (less gravity, pressure difference), but the basis for the maths is the same.

Post-hoc sarcasm tag. However, rocks can behave in unexpected fashions.

Quote
Cutting into a mesa like in Red Mars which was mentioned upthread is another valid idea, although subject to the questions of rock competency I would ask.

Cutting into a mesa is cutting into bedrock.

There's a distinction between competent and weathered bedrock which is why I bring it up. The walls of a mesa or plateau are a continually weathering face (or at least weathered and then stopped, in the case of Mars). Generally (though I'm no geotechnical engineer), you can throw concrete at bad ground, I'm just saying it won't be a straightforward exercise.

Quote
Lava tubes are there, vitrified and easy to seal.

The latter is debatable. We don't know how structurally sound any tube would be, how permeable/airtight, how clear. We'd have to do the same engineering analysis as with any underground work. (The advantage is that it is, nonetheless, pre-dug.)

As I've mentioned many times, my favourite part of lava tubes is that anything underground will have a temperature that is the average of the surface temperature (heat-pulses mush together the deeper you go). For most places on Mars, even at the equator, lava tubes would be below freezing. Hence water vapour that heats up on the surface will freeze out in the tubes. I suspect that a short way inside from any skylight or breach will be a solid plug of water ice. (Maybe CO₂ as well, depending on the temp.)

Radiation shielding, huge excavated volumes, water in a nice solid filtered form. What's not to love.

Well, most lava tubes run down at a slight angle, especially in the Tharsis Montes regions. There would also be slope winds from the diurnal pressure changes which I'm guessing would cause the tubes to "breathe," carrying water vapour in or out. So an ice plug does not sound at all out of place.

The issue with tunnelling as a solution is that people see a TBM and think it's just this one machine which makes holes, when in fact it's an entire construction solution with the added complexity of a TBM.

But the tunnels are lined with precast concrete blocks made on the surface and sequentially bolted into place. There's gravel and grouting between the tunnel wall and the blocks.
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Offline MickQ

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Re: Envisioning Amazing Martian Habitats
« Reply #1556 on: 12/07/2018 08:55 AM »
Also not being a Geotechnical engineer, I'm wondering if a good place to tunnel would be the base of a five or six kilometre high cliff in Valles Marineris.  Would this likely be Competent Bedrock ?

Offline Lampyridae

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Re: Envisioning Amazing Martian Habitats
« Reply #1557 on: 12/07/2018 09:25 AM »
Also not being a Geotechnical engineer, I'm wondering if a good place to tunnel would be the base of a five or six kilometre high cliff in Valles Marineris.  Would this likely be Competent Bedrock ?

It would mostly be loose rocks and soil for several hundred metres. The deeper you tunnel towards the actual base of the cliff, the higher the pressure over your head. By the time you are directly underneath the top of the cliff, you have the equivalent of two kilometres of Earth rock bearing down on you. At those depths, rock is basically plastic and tunnels are eventually squeezed shut.

But Valles Marineris is not actually a cliff, more like a medium slope (20 or so degrees) in most places. The vertical scale is heavily exaggerated in the 3D flyarounds you see.
« Last Edit: 12/07/2018 09:41 AM by Lampyridae »
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Offline MickQ

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Re: Envisioning Amazing Martian Habitats
« Reply #1558 on: 12/07/2018 09:38 AM »
Well, there goes my plans to BASE jump off the top.

Anyway.  In that case, what about somewhere a little smaller, like Ius or Euchus Chasma ?

Offline Lampyridae

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Re: Envisioning Amazing Martian Habitats
« Reply #1559 on: 12/07/2018 10:07 AM »
Well, there goes my plans to BASE jump off the top.

Anyway.  In that case, what about somewhere a little smaller, like Ius or Euchus Chasma ?

That's a bloody good question which needs answering. Generally slopes on Mars are like maximum 45 degrees due to scree buildup and so on. But knowing where really steep slopes would be is also useful. I'll use MOLA data to try figure it out. Actually, no... it'll have to be HIRISE stereo because MOLA data points are ~400m apart.

The cliffs in Echus Chasma are four 2.5 kilometres tall (slope is ~45 degrees):



Then there are the steep, smooth cliffs of the North Pole region. These are about two km tall (but I suspect actually 800m), slope is ~80 degrees:



You could ski your way to a BASE jump  ;D
« Last Edit: 12/07/2018 01:20 PM by Lampyridae »
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