It's very hard to find shelter from an arty stonk in OFP.
Possibly your best bet is to run a looping repair/heal script while the strike is on
? 0.3 < getdammage _unit < 0.9: _unit setdammage (getdammage _unit-0.3)
syntax guaranteed to be wrong, but hopefully you see what I'm getting at ... you don't resurrect dead units, but injured ones have a much better chance of surviving. You can do the same trick with buildings.