It's not just the KP bridge,but all the bridges on all the maps,fences too.
I once had a German APC become immobilised on the KP bridge and sent another APC to push it off the bridge onto the other side of the river and it almost worked till I got to the last few meters of clearing it off the bridge then the bridge collapsed
.It didn't completely collapse just the flooring disappeared leaving the pylons in place and my 2 APCs suspended in mid air,after about 5 minutes the good APC that wasn't immobilised fell into the river.
Bridges in this game are funny and should be looked at along with fences(I had a T-70 get upended by a fence).
Some of the bridges are missing the last section of the bridge making it immpossible to cross both ways(Rakitnoe map) and this also applies to the 2 bridges on that map at the extreme edges.I'm able to cross them from S to N,but not N to S.Yes I'm able to utilize them during the tactical battle by giving the road movement command and setting the movement point at certain areas.