At the moment the condition of stands and runways goes down every time they are used.
As far as I can tell, it does not vary. It should.
A small aircraft should cause less damage than a medium aircraft, a large aircraft more than a medium aircraft.
A small aircraft should cause more damage to a grass surface than a paved surface.
Since a concrete stand is more expensive than the asphalt one of the same size, the concrete one should be damaged slightly less (smaller difference than the difference between grass and asphalt) by each use than an asphalt one.
I think ihe damage should vary in the following ways:
Based on surface:
Grass most damaged by each use.
Asphalt in the middle.
Concrete least damaged by each use.
By aircraft size:
Large aircraft cause the most damage with each use.
Medium aircraft in the middle.
Small aircraft cause the least damage with each use.