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So far the best solution I've seen to this sort of thing (other than building a taller bridge) is the waterfall approach. Probably a bit spensie for some rando railroad bridge but it's clever nonetheless.

https://www.dailymail.co.uk/video/news/video-1008464/Amazing...

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I've often seen large gates with hanging chains at the maximal height just before low bridges and tunnels. Wouldn't that also be pretty efficient, reliable and not requiring any maintenance? I suppose having an obstacle spring in front of you would be even more likely to make you stop, but if you're still going when some chains hit the top of your vehicle you deserve to have your license suspended anyway.

The trouble with 11foot8 in particular is that it’s right on the intersection, so through traffic passing by the bridge without going under it would hit the chains as well.

But that bridge in Australia isn’t on an intersection. There’s plenty of room for a hanging bar.

The point is not to avoid damaging the trucks, it is to prevent the trucks damaging the bridge behind the barrier.

Here's an example from 20 miles away on a spur line of what kind of bridge damage can result: https://www.wral.com/17469149/

The road and railroad were only closed for 4 days, but it's clear that if the truck in this incident had a bit more momentum, the bridge could have been removed entirely.

There is a low bridge in Albany Oregon (near me) with hanging chains. The bridge is still beat to crap from all the collisions.

I mean if you think like a rational person, a big "LOW BRIDGE" sign with blinking lights should be blatantly obvious, but it's not.

That’s really cool. Is that a divided highway? How do the trucks back up and turn around there?

They have them in more than one place, in some cases they have to stop traffic so the truck can back out.

That's pretty neat, but what does it look like during broad daylight? Is it only really visible at night?

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