In a C152, I find that anything over 40kts becomes difficult to taxy in, with brakes frequently needed to keep the aircraft going in a straight line when taxying cross-wind. This is on a hard surface. I wouldn't let a student taxy in more than about 30kts without me sat next to him.
It is my experience, in a C152, that they don't have any tendency to tip over if the controls are used incorrectly - but directional control is made more difficult by not having ailerons held correctly. Incorrect use of elevators doesn't seem to have any noticable effect whilst taxying, but I'm sure the engineers would disagree!
I find that controls should normally be held as if for a head-wind (back-pressure, and ailerons into wind) even in a tail-wind of up to about 30kts, because the propwash means that the controls are experiencing a headwind even if the actual wind is from behind. I tend to find that the elevators start becoming reversed with about 25kt of tailwind (need to hold them forwards in more than this) and the ailerons with about 35kt (need to hold them away from wind rather than into it). I can't explain why the ailerons reverse after the elevators - logically, they should reverse first as they are not affected by propwash. Maybe someone else can explain? Of course this will vary from one type to the next.
As for damage, assuming you can stay on the taxyway, the thing which will damage your aircraft is not keeping a tight hold of the controls. They will bang around in the wind, especially a tailwind, and it's the banging against the stops which will do the damage.
The most extreme wind I've ever experienced in a C152 (well, I was outside actually) was 50kt. We realised the wind wasn't going to die down, so we went to put the aircraft back in the hangar. It was parked facing into wind, which was fine, but we needed to turn it 90 degrees to back it into the hangar. We turned it, but as soon as we started pushing it backwards the wind caught the fin and tried to turn it back into wind again, even with the nose-wheel pointing fully in the oposite direction. In the end the only way we could get the aircraft into the hangar was to have one person pushing on the downwind side of the tail, stopping the aircraft from turning, while another person pushed the aircraft backwards into the hangar.
FFF
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