From earlier this week… Freight bridges are usually very well maintained, but things do go wrong. UP Train Derails, Catches Fire on Bridge: Report.
The stories of the incident are not too enlightening, but if you click thru, the images that accompany this story are pretty amazing.
“At around 6:15 a.m. PT, July 29, a Union Pacific mixed freight train derailed on a bridge in Tempe, Ariz.,” UP said in a statement to Railway Age. “Eight to 10 railcars were on fire. The south side of the bridge collapsed and railcars fell into an empty park below. The bridge received its annual inspection July 9, 2020. The Phoenix Fire Department is on the scene. One person was treated for smoke inhalation. The train crew is uninjured. Three tank cars were on the ground under the bridge. Two contained cyclohexanone; one contained a rubber material. None are reported leaking, and no tank cars were involved in the fire. The cause of the derailment is under investigation.”
While it is a steel-truss bridge on concrete piers, it seems that there must have been some timber in the railroad’s construction for the fire to burn the way it did.
UPDATE: A section of the damaged bridge was taken down with explosive demolition. Portion of Tempe Town Lake bridge damaged in train derailment detonated.
Crews on Sunday detonated a 150-foot portion of a bridge over Tempe Town Lake, which was damaged in a train derailment last week.
You can’t expect reporters to get the words right; not when they have to do with anything technical. But the video is worth clicking thru. It’s explosive demolition!
UPDATE: It seems one of the tankers did leak. What is cyclohexanone? The chemical that leaked during the Tempe train derailment and injured 2.
Five hundred gallons of Cyclohexanone leaked before they could turn the tanker upright and contain the spill.
Cyclohexanone is frequently used in the production of nylon and is highly flammable. The chemical’s flashpoint is just 111 degrees, meaning the vapors will ignite if given a spark or open flame at that temperature.
The flashpoint is a point of concern for Glass as temperatures in Phoenix reached a scorching 118 degrees on Thursday.
It is apparently also a skin irritant, and can be an issue if the fumes are inhaled.
The 2 minute video at that last link isn’t annoying.