What's the biggest dome we can build on the Moon from the structural standpoint?

Very large!
The dome would have to be weighted down to avoid exploding from internal atmospheric pressure. Arthur C Clarke envisioned domes built from native rock (cheap) and quite thick to provide the needed weight. Stone is strong in compression. Today we know that it would also double as radiation shielding and provide thermal inertia during the long days and nights.
The rock would't even have to be airtight. Plastic sealant could be sprayed on the inner wall while the rock provided structural strength.

Even though a dome could be hundreds of meters across, it would probably be safer to put a city beneath several domes with airlocks between.

We don't need to build a dome, the moon has lava tubes big enough to hold cities:
purdue.edu/newsroom/releases/2015/Q1/theoretical-study-suggests-huge-lava-tubes-could-exist-on-moon.html
onlinelibrary.wiley.com/doi/10.1002/2017GL074998/abstract

Enjoy your collapse and swift death.

What swift death?
They will die 6 times slower than on Earth of they didn't already suffocate to death.

Good point

Enjoy your slow motion collapse and long drawn out painful death.

We could make a dome so big it'd be a sphere. We could enclose the whole damn moon in a steel sphere 1 meter thick covered in lunar regolith to weigh it down
google.com/amp/s/www.nextbigfuture.com/2016/12/beyond-dome-city-colonies-to-shell.html/amp

The most recent lunar volcanism was something like 1 billion years ago. These tubes have been stable for millions of years and are likely to be stable for millions more.

Ok, the last step is to dispose with the Moon entirely and build a habitat out of asteroid.

Until you start building cities in them.

You're on the moon, where do you get the air from?

I dunno. You could get hydrogen and oxygen from the ice but that would be dangerous as hell.

Fuck that, just build a new moon that's hollow like the earth is.

Just move to the next pool over.

>air is hydrogen and oxygen

>doesn't understand that you can live in a low pressure O2 only environment.
There is no good way to get nitrogen on the moon.

>being this retarded
you can do both, the moon has more material than the entirety of the asteroid belt, so mining it would be greatly to our benefit

Oxygen is highly reactive. Having an open environment that is 100% oxygen is problematic. Even if it's low pressure.

>You're on the moon, where do you get the air from?

Ship it up from Earth. The liquid to gas expansion ratio is 1:694.

what if the dome leaks?

building in them should be fine as long as you don't build on them.

build self sealing domes.

Patch the hole.

>what if the dome leaks?
Then you use leak detection techniques and patch it and keep a reserve supply of nitrogen on hand for when it inevitably takes places. A large bullet hole in a large martian dome would take about two weeks to depressurize.

The Moon contains all the same elements as the Earth, just in greater or smaller amounts. Dig underground and you will find minerals containing nitrogen. You will also find argon, which can be used to provide an air mixture also. Oxygen is so easy it's a non-issue, you're going to be making millions of tons of it as a by product of refining metal oxides. You can mine water from ice deposits in permanently shadowed craters or from mineral deposits deep underground.

Eventually it'd probably be a good idea to ship in volatiles like nitrogen from captured comets and asteroids. That takes a lot of effort though, so it'd better be worth the expense.

lol is this what flat earth people believe

why can't I see the ice wall from where my house is hmmm?