Sintered Brick Construction
Sintered Brick Construction
If construction of an enclosed space can wait until there is a little industry established upon Luna, then a roof can be supported by locally produced sintered regolith brick with locally produced fiberglass reinforcement. Step 1: Dig a ditch with a bottom semicircular in cross section and sized to contain the desired building. Step 2: Place a circular construction frame at the end of the ditch. Step 3: Place sintered bricks in frame to form a circle of bricks that have been shaped for making that size circle. Step 4: Band the circle of bricks together with several turnings of fiberglass cord that fit in preformed notches on the outside of the bricks. Step 5: Remove frame from brick circle and tamp regolith between brick circle and bottom of ditch. Step 6: Use brick circle as a frame for adding inner brick circle one half brick further down the axis of the cylinder with its own reinforcing fiberglass cording using bricks specially sized for the inner layer. Add alternate inner and outer brick circles until the ditch is full of a brick cylinder. Add door sections at the cylinder ends and cover the structure with regolith. Spray the interior with a layer of locally produced liquid glass and then with a layer of locally produced liquid aluminum. Then fill the building with atmosphere. This building could be built entirely by remotely operated devices and will not collapse from a mere loss of atmosphere accident.
The atmosphere contained in a building might be air, hydrogen, or nitrogen depending upon the industrial use to which the building will be put. Naturally personnel must wear self contained isolated breathing apparatus (SCIBA) when working in buildings with non air atmospheres. A reason for a non air atmosphere in a building would be the use of the building to construct devices intended for service in the ambient lunar vacuum which devices contain electrical or structural alloys that would corrode in an air atmosphere. Sodium could be used as an electrical conductor or as a solder on equipment for vacuum service as long as the temperature of the equipment is kept low enough that sublimation of the sodium does not become a problem. Sodium would probably be put to such use in alloys so that if sublimation did occur to any substantial extent, a film of the other alloy elements would form to stop the sublimation. SCIBA equipment would include rebreathing technology to prevent exhaled air and moisture from entering a building's atmosphere.
When Should People Arrive?
The ability to use various locally available resources (ISRU) to support human life suggests that it would be better for people to arrive on Luna after these resources become fully available. This can be the case if industry is initially established by remotely controlled manipulators and other devices. If one considers the inconvenience (from management's point of view) and expense of working with remote controlled manipulators with a three second response time as compared to the inconvenience and expense of providing air, food and water costing more than its weight in gold to employees on Luna; then one might see the logic in developing local life support resources before the first people arrive.