I'm sure that I read somewhere that they deliberately took a sledgehammer to the bridge set for Generations, in order to really show the damage of the saucer crash. The end of that movie shows the familiar set in a pretty bad state of disrepair. So no, it seems that almost nothing of the Ent-D bridge survived - although the Reeves-Stevens' once claimed that the wooden "horse shoe" was retained. No idea what happened to it, though.
I believe it's at "The Hollywood Museum," or at least it was at one point