At what point are bridge guardrails used (required) ?
I’ve noticed many railroad bridges over roads don’t have them yet many if not all over water do. Is it something based on height or length of the bridge or what they are crossing over ?
Mark.
That’s an interesting question Mark.
Unfortunately, I don’t have an answer. Could it have something to do with the probability of human traffic?
Karl
My GUESS would be that they are used whenever the loss of property is greater than the cost of installing and maintaining them. Example: If a train derails crossing a highway overpass, the train could fall to the roadway, but is easily cleaned up by cranes and such, and is not likely to cause a LOT of lost revenue. Where as, Like the case of Amtrak a few years ago, if a train derails on a river overpass it could fall into the water, requiering “specilized” clean-up, ie-Divers and Barge Cranes (not highly accessable) or damage a very expensive(cost and lost revenue) bridge.
Just a GUESS.
Like this?
There were/are guardrails on the bridges here, but those obviously didn’t stop the two cars that went off here. Fortunately the only car at the intersection was stopped across the intersection from the crash for the red light.
Kevin
I’ve wondered about this too. I’ve seen them in a few tunnels and on open track that winds around the side of a mountain.
I guess, they check the chance of a derailment. If you have ballasted track, you may go more easy without guard rails.
I’m looking for someone who knows it!
Wolfgang
Are we talking guardrails on the sides of the bridges or between the running rails?
Kevin
We’re talking about guardrails between the running rails, not safety railings on the sides.
Mark.