Wouldn’t it be nice to have a habitat to live in when you first arrive on the Moon rather than spend a month living in the cramped lunar module while you build your first habitat? With enough adaptability in your robot or remotely operated machinery, the machines should be able to work around problems that come up — and problems always do. They can spend weeks or months building facilities before people arrive.

The discussion had moved away from the idea of sending a prefab habitat for the first mission crew (missionaries?) to the idea of laying brick or concrete, using in situ materials rather than expend the resources moving all the materials from the deep gravity well of the Earth. Either way, it would be more productive for the crew on the Moon to be doing science and other things that are not as repetitive as construction or brick making. It costs a fortune to put people on the Moon, so they might as well be productive in ways that robots and machinery are not.

I suspect that the reality is that first-generation habitats will be sent to the Moon from Earth, requiring minimal construction effort, second-generation habitats will be made with in situ materials, and third-generation habitats will be made with more advanced refining of in situ materials and more advanced construction techniques.

We need to get material engineers (and not) on the moon and let them play. Allow people to own what they build and the optimum methods/designs will soon rise to the top.

We barely have self driving cars now. When we have self driving semis that refuel themselves and load and unload themselves then we MIGHT be close to having automated construction machines.
On earth but not in the remotes of space.

Man will pave the way for robots.

Manpower and intelligence is ready today.

I had been thinking of sealing the interior, but your idea of recovering as much water as possible is good.

Except that cement is a little porous. So air will escape. Plus it might crack during curing and or drying;

So my idea keeps the sealed dome bag on the outside. Plus my idea lets you recover as much as possible of the valuable water.

The point being that what seems funky can be functional.

(The least processing one can get away with.)

pivoting slightly–This is an intriguing methodology: “Earth-bag” construction.

Underground Earth Bag Building Ep 3
Building Considerations – Strengthen the Walls
https://youtu.be/pRkD3Nb-U0E
(8:39)

Drop onto the surface temporary shelters that inflate. Bigalow can provide these today.
Someone has to go up and flatten the ground with ‘earth’ movers so larger structures can be installed.

I truly think a thinner than normal Bigalow dome could be the form for a spray coated concrete liner.
Using gravel sized regolith as your aggregate would make the concrete cheaper to produce and most of the water would be recovered during and after the curing process. A simple dehumidifier does the water recovery so it can be recycled into the next load of concrete.

As your permanent domes are hardened and finished just cover them with several feet of sand sized regolith for further micrometeorite protection.

Connect the domes with flexible tubes in case of lunar quakes.

The brick idea is fine. But in order to not use a hardening mortar you have to shape the drinks a little like Lego blocks. A pair of ‘posts’ on the top of each brick and a pair of sockets in the bottom of each brick. Sand in between each brick.
The bricks would not be solid but would float a little.
You could shape the bricks so they form arches and domes better.
You could form arches over the flexible rubes and then cover those arches with regolith.

For power, a simple steam generator would be self-contained with proven technology having off-the-shelf reliability and low maintenance. The temperature in the lunar sun is 250°, just enough to boil water that would otherwise be sitting in a storage tank somewhere.
When the sun goes down for 14 days, perhaps it would be better to be underground and insulated against the 300° below zero temperatures on the surface.

I’m seriously doubting initial settlement of the Moon is going to take the form of 2017 America, with sleek, brushed-aluminum interiors, back-lit by Solar FREAKIN’ roadway technology lights.

These structures will be made by planting a complete manufacturing system package which will have solar and probably some sort of “safe” nuclear power generation system (or an ECAT?) on the surface of the moon. I assume initially they will be complete inflatable enclosures that could be covered by local material for protection and then there will be enclosures dug deeper into the surface that will be more complex and made in one complete sealed and bonded enclosure. And then there will be the tunnel potential, if they are determined to be stable.

We will have to bring some level of material initially but the goal will always be to develop on site manufacturing capabilities both metals and ceramics, gases and liquids. These robots will be flown to a location and will autonomously set out to build these sites readying them for human inspection and habitation.

It has shown that the concept of concentrating solar radiation to heat the material into some form of construction material is likely valid, rather than depending upon electrical generation.

It has shown that at the temperatures reached, merely heating lunar regolith in place will not create the lunar roadway surfaces that have been envisioned by some. It has not answered the question of what temperature is needed for this road-building process, or whether this process is feasible.

It shows that lunar soil can be formed into construction material of some amount of strength, although a greater strength or reduced friability may be desirable for construction.

Garry is correct. This is only the start of the investigation into practical lunar construction using in situ materials, rather than materials lifted out of Earth’s gravity well.

Cotour is correct. Just as on Earth, local materials are the least expensive to use for construction. I recall driving on a highway that has a pink hue, in northeastern Minnesota, because that is the color of the local rock.

I’m thinking more 1st/2nd-generation local (Moon) manufacture of such items, on a survival/establishment basis.
The brick might not be the best building material format to conceptualize for the Moon. We would also need a Moon conducive method to mortar the bricks together.
–My house basement & foundation for example, all poured concrete. Cool & quick process– dug the hole, set up forms & re-bar, and pumped a slurry of cement into them.

Autarky will, of course be a long term goal for Moon settlement. You do however triage vital implements/resources and bring them along, whether it’s across the Great Plains or Space. As you establish indigenous capability, you can import less.

To say however, that *any” imported raw materials required, would be a non-starter, is to understate the problem.

Referencing electricity requirements for any sort of industrial-process at scale; solar panels aren’t up to the job. Making aluminum for example, is electricity intensive.
And most common chemical-reactions don’t occur at ambient Moon (or Earth) temperature.
On the upside however– the vacuum of the Moon presents a number of advantages.

I’d prefer to “make brick on the Moon,” with the lowest level of technology that can get the job done, and I’m doubting that involves laser’s, which would have to be imported as well.

But, who knows? -I don’t claim to have the solution, I only play a Materials Engineer, on the interweb.)

and..trying to be cognizant of the First Rule of Space Advocacy, “You aren’t allowed to rain on other people’s parades.”

The challenge is to process the existing material on the moon or where ever you happen to find yourself. To create a system that needs any raw materials imported to the moon, or an asteroid, from the earth is a non starter. Turn solar power into electricity in order to extract Water / Oxygen / Hydrogen etc. and then using the electrical power producing ability to drive machines I.E lasers in order to melt and combine the materials found on site is the winning model.

LocalFluff: The reason I demand courtesy and good language is to force the commenters to raise themselves up from animals and savages. If someone can’t behave like a civilized and thoughtful person and has to descend to curse words and insults, then they really don’t belong here.

They might want to re-define what they call a “brick.”Let us not forget, “bricks” have to be fired to chemically fuse together. You mix a pre-screened clay type mineral together with water, which has to be extruded into a mold to form, and then energy must be added to complete the chemical-reaction. Load-bearing bricks don’t “dry,” they have to be fired.

Brief History of brickmaking in the United States
http://brickcollecting.com/history.htm
(with links to modern day manufacturing techniques)

And this: https://youtu.be/WzmCnzA7hnE

Although this is a more complex solution I think it might be faster and achieve better quality control. Sometimes the simplest solutions are just too simple. This technology seems too simple to me.

LocalFluff: Watch your language! I do not tolerate cursing or four-letter words on Behind the Black. Do it again and I will be forced to consider banning, even though I would regret it.

Just a few hundred yards from my home, there are cows who “3D-print” bricks like that every day.

About 24 minutes into this video (sorry for the horrible video player they insist on using at SSERVI), an experiment is mentioned, in a passing way, that concentrated sunlight on Lunar regolith in an artificial methane atmosphere. Solid iron just pops up out of the ground! Solid metal is much easier to handle than any ceramics. Our Moon is an iron Moon! Exploring it will dawn the second iron age.
https://connect.arc.nasa.gov/p3vb1u5ijgy/?launcher=false&fcsContent=true&pbMode=normal

I have no idea what that substance might be; it would have to be very cohesive, require only a thin coat, and allow bonding to whatever is going to serve as the mortar. Perhaps the coating could be applied by 3D printing. Of course, it would also have to be usable in a vacuum, withstand extreme temperature changes, etc.

This looks like the first of what may be a huge number of steps before anything practical is realized. We have to start somewhere.