Setting: 2100's ~20 years after Nuclear Armageddon, Carlsbad NM area
I'm hoping to get advice on an underground complex about structural stability, ventilation, proportioning, construction requirements, and similar. Specifically about an underground housing/apartment complex, Los Lobo Loco (the Crazy Wolf), housing nuclear wasteland "adventurers" (monster hunters, mercenaries, scavengers/explorers, mages, and similar).
The floors in the Wolf are built circularly with a central common room that is connected to an inner ring by eight radially branching halls, and then an outer ring connected to the inner by 24 halls. The area between the outer-inner ring and along the outer-most wall are used the housing. The area between the common room and inner ring are rented work spaces or public facilities such as gyms, conference rooms, rented secured armory, target range, and anything else an adventurer might have need of.
1: what would be needed to keep the facility ventilated?
2: how stable would the structure be?
3: what would be a reasonable max resident capacity (per floor)?
4: what would be required to expand the Wolf? would it be better/safer to expand down or build additional outer rings? (it under goes expansion over the course of the story and during the 20+ years prior)
I have done research on mine construction, building ventilation, and but would like advice from someone experienced om the field.