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Sadly, there's not much that can be done to fix humans. The elevenfooteight bridge now has a traffic light which goes red and stays red on detecting an overhei

Sadly, there's not much that can be done to fix humans. The elevenfooteight bridge now has a traffic light which goes red and stays red on detecting an overheight vehicle, with a lit-up sign saying "OVERHEIGHT MUST TURN". It's still getting hit by overheight vehicles. And then there's the lengths that had to be gone to in Syndey to stop overheight vehicles entering tunnels: https://www.youtube.com/watch?v=NoTMC-uxJoo https://www.youtube.com/watch?v=NoTMC-uxJoo

vanattab 10y ago
That water curtain stop sign is brilliant.
- Terr_ 10y ago
  The next best thing to holo-signs: A visual barrier, but won't actually harm you if you hit it.
  - vl 10y ago
    Brilliant, but unfortunately increases stopping distance.
    - tombrossman 10y ago
      The water is right at the tunnel entrance, not in the area where you would be braking to avoid impact. By the time you've reached the water you will have collided with the top of the tunnel, which should go a long way towards helping you slow down. Literally 'idiot proof' design right there.
mikeash 10y ago
It depends on what you want to fix. The 11'8 bridge does indeed seem a lost cause as far as preventing people from ruining their overheight vehicles. But the problem for the bridge has been solved: they installed a beam in front of the bridge which takes the impact. The same sort of thing could be done with this bridge. Install a sturdy beam ahead of the structural bits. You won't stop people from driving overheight vehicles onto the bridge, but you will stop them from destroying the bridge in the process.
- maxerickson 10y ago
  It depends on if you want to allow max height vehicles to use the center lanes or not. I guess you could have a mechanism to raise the warning beam and only activate it after direct communication with the driver.
  - mikeash 10y ago
    You could have sacrificial beams in front of all the important ones throughout the bridge, if you're worried about lane changes. That may not be worthwhile though.
    - maxerickson 10y ago
      My (not well studied) understanding is that all of the beams are important on this style of bridge. That's sort of the other way of looking at the problem. The bridge isn't overbuilt enough.
      - mikeash 10y ago
        Right, so you'd need a lot of sacrificial beams if you wanted to defend against lane changes in the middle of the bridge. Probably easier to add structural redundancy instead.
caf 10y ago
There's a whole page about the Montague St bridge in Melbourne: http://howmanydayssincemontaguestreetbridgehasbeenhit.com/ http://howmanydayssincemontaguestreetbridgehasbeenhit.com/

vanattab 10y ago

That water curtain stop sign is brilliant.

Terr_ 10y ago
The next best thing to holo-signs: A visual barrier, but won't actually harm you if you hit it.
- vl 10y ago
  Brilliant, but unfortunately increases stopping distance.
  - tombrossman 10y ago
    The water is right at the tunnel entrance, not in the area where you would be braking to avoid impact. By the time you've reached the water you will have collided with the top of the tunnel, which should go a long way towards helping you slow down. Literally 'idiot proof' design right there.

mikeash 10y ago

It depends on what you want to fix. The 11'8 bridge does indeed seem a lost cause as far as preventing people from ruining their overheight vehicles. But the problem for the bridge has been solved: they installed a beam in front of the bridge which takes the impact. The same sort of thing could be done with this bridge. Install a sturdy beam ahead of the structural bits. You won't stop people from driving overheight vehicles onto the bridge, but you will stop them from destroying the bridge in the process.

maxerickson 10y ago
It depends on if you want to allow max height vehicles to use the center lanes or not. I guess you could have a mechanism to raise the warning beam and only activate it after direct communication with the driver.
- mikeash 10y ago
  You could have sacrificial beams in front of all the important ones throughout the bridge, if you're worried about lane changes. That may not be worthwhile though.
  - maxerickson 10y ago
    My (not well studied) understanding is that all of the beams are important on this style of bridge. That's sort of the other way of looking at the problem. The bridge isn't overbuilt enough.
    - mikeash 10y ago
      Right, so you'd need a lot of sacrificial beams if you wanted to defend against lane changes in the middle of the bridge. Probably easier to add structural redundancy instead.

caf 10y ago

There's a whole page about the Montague St bridge in Melbourne: http://howmanydayssincemontaguestreetbridgehasbeenhit.com/ http://howmanydayssincemontaguestreetbridgehasbeenhit.com/