Comment by woodruffw

9 hours ago

I think the physics of the situation don't make a barrier feasible: a derailed train going >100 mph is going to transfer a lot of energy to any kind of barrier it impacts, which in turn might exacerbate the situation (by spreading debris).

I think these kinds of accidents are largely mitigated by rail defect monitoring. I know rails in the US are equipped with defect detectors for passing trains; I'm surprised that a similar system doesn't exist for the rails themselves. Or more likely, one does exist and the outcome of this tragedy will be a lesson about operational failures.

In principle only, if a barrier could keep a train on its side of the barrier, scraping along the barrier for a long distance instead of smashing headfirst into it, the energy could be dissipated over a long period of time, preventing fatalities. But what kind of barrier can withstand a train?

  • This collision happened precisely because of unfortunate circumstance that break in the rail and derailment happened just before the switch leading to the opposite track. Without the "help" of the switch, carriages of the first train likely wouldn't have invaded the second track.

    • The tracks are less than 3m from each other, a derailed car doesn’t need to get very far to be a risk to incoming traffic.