No, China won’t do much if any bridge-blowing. First, it’s not a very effective tactic compared to the alternatives. Bridges are extremely strong (for obvious reasons) so it’s not actually easy to take most of them out with conventional weapons. Second, the US has an extensive road network with many alternate routes.

What China would actually do to hobble our logistics is bomb our seaports and data centers. This is much easier, much more effective, and these are vastly harder to do impromptu repairs on.