Crumbles when soft

"Sintering" to make concrete is a process needed on Earth owing to our humid environment. Lunar regolith will "set up" as concrete by just adding water. It has been in a high vacuum for billions of years and all of the water, if there ever was any, has been driven off. The same would likely be true for asteroidal materials. I am not sure about the materials on comets. But this also suggests in at least the long term (and I don't know what long term means here) concrete in space will not hold together as it loses its water. At least not without a coating to prevent water loss to space. But why use concrete (which as I interpret it means using lots of water)? Water is cheap on Earth, but not in space. But solar power is cheap in space. Why not sinter to make ceramics and forget the concrete? Or use metals, which can be vapor deposited using focused sunlight, which can reach 6000 K and so could vapor deposit any (and all) element(s).
Sincerely, Jay Huebner

Re:

>little space crafts like flying containers with arms
>or flying scoops with hatches) would deliver the materials
>(sands, water,cement) to refining and processing units in
>space from where the different materials get to the space
>based rotating cement/concrete mixer units."
>
>To make concrete you still need to sinter some rock to
>make cement so you will need a fair bit of power.

1. Sintering* is, I believe , a process used in the formation of
'Syncrete', but I doubt that it can be used to form a "cement"
which can be mixed with sand & water to any good purpose.

2. >(sands, water,cement...rotating mixer>) sounds too much like
earth-style Cement made from Limestone, a biological product
not found in space.

3. Will someone please post the chemistry and procedure for making
and molding/forming Syncrete and help us to make the resolution
never to use the generalized and misleading term "Concrete" in
lieu of "Syncrete" ever again!

Bob H.

[*] Dictionary.com sez:

/v./ *sintered,* *sintering,* *sinters *
/v. //tr./

To cause (metallic powder, for example) to form a coherent
mass by heating without melting.

/v./ /intr./

To form a coherent mass by heating without melting.