If you put an above ground pool in the ground what about rust maintenance and the pressure on the walls from the dirt?

Yes you can. Installation as follows: Steel mesh brace (galvanised), steel plates (galvanised), split hose for the top of the steel mesh. Pop rivet steel plates together. Cloth ducktape over pop rivits will give a smooth finish. My pool lasted 10 years, required a new liner and still the mesh was in tact. The steel plating required little bit of treatment, but not severe.