This one is all steel. However, there is a wood trestle about 200 yards north of where this derailment took place
New Orleans has a wooden trestle that is miles long, raising the track from ground level near the stadium downtown up to crossing the Huey Long bridge. I have ridden Amtrak over this bridge many times and it scares me to death. I was in New Orleans just a couple of months ago, and still see freight cars parked way up high on this trestle. If one of those supports goes down, yikes.