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11 Foot 8 – The Can-opener Bridge
131–140 of 216 posts
Re: 11 Foot 8 – The Can-opener Bridge
#132This problem is already solved. The steel beam rakes off any overheight bits allowing the trucks to pass through.
Thank you so much for this. Very well delivered.
Re: 11 Foot 8 – The Can-opener Bridge
#133Earlier quoted context omitted.
I never understood the high-tech approach to this problem. Where i am from they have large metal tubes dangling down a ways in front of the bridge. Makes it sound like you have already hit it. Another more insistent approach I have seen elsewhere is to mount a large steel bar across the road, which takes the top of the truck off before they hit the bridge. (edit:not very simple problem, obviously..)
Friendly bit of advice, you may want to work on your hubris. In general, when a group of experts implements a complex solution there is a reason for it. Rather than reveling in your ignorance and feeling of superiority you may want to instead research those reasons. Fyi, others in this thread have listed them.
Wasn't meant to read as hubris, I genuinely was curious (if a little unclear).
FWIW I have read about this at length generally at a local level, living and working next to a couple of bridges with this issue. A high tech approach has been tried and abandoned with these bridges as they were (fatally) not effective (though not this high-tech). I naturally assumed there was some particular reason for the tunnel.
I read the rest of the thread before I commented, the ones you point out were written after, and they do indeed go some way toward explaining that particular issue at that particular tunnel. The original post did not explain anything but the bad road design.
While we are giving friendly advice, your comments may be better received if you gave them in a spirit of generosity, as I have taken yours, rather than jumping straight to judgements and epithets.
Re: 11 Foot 8 – The Can-opener Bridge
#134I used to work really close to where this bridge is at my last job and many of my coworkers had worked in offices even closer previously. Supposedly, every time there was a crash people would rush to observe what happened even though it was a fairly common occurrence.
The bridge is located in a kinda odd space to do construction. While I imagine it's possible to retrofit or dig it to be deeper, it likely would have been really inconvenient to the adjacent businesses.
Re: 11 Foot 8 – The Can-opener Bridge
#135I used to work really close to where this bridge is at my last job and many of my coworkers had worked in offices even closer previously. Supposedly, every time there was a crash people would rush to observe what happened even though it was a fairly common occurrence. The bridge is located in a kinda odd space to do construction. While I imagine it's possible to retrofit or dig it to be deeper, it likely would have b…
They actually raised the bridge another 8 inches recently. The 11foot8 channel covered a lot of the work being done and stuff.... and the 12foot4 bridge still gets new victims from time to time, just less often.
Re: 11 Foot 8 – The Can-opener Bridge
#136Earlier quoted context omitted.
Why cant they put a swinging bar at the tunnel height some distance before the tunnel? The bar knocks the top of the truck and wakes up whoever is driving to the fact that the truck is too tall.
Or a wedge barrier: https://eci-illinois.com/wedge-barrier-versus-medium-size-tr...
In my professional engineering opinion, this is very badass.
Re: 11 Foot 8 – The Can-opener Bridge
#137The Sidney Harbor Tunnel had a similar problem. They came up with an elaborate but successful solution.[1] There are detectors and huge flashing warning signs that light up. Then, there's the last-chance sign. At the entrance to the tunnel, pumps force a curtain of water straight down across the entire roadway. Then a powerful laser system projects a giant octagonal red STOP sign onto the water curtain, filling the e…
They tried an electronic warning sign that lights up when a truck is too tall, but drivers still can't resist the lure of the hungry bridge: https://youtu.be/YQssl0sM9As?t=6 , https://youtu.be/cZrOcCXNq5c?t=5 , https://youtu.be/iQfSvIgIs_M?t=32 Might have been better off erecting a giant, no-tech billboard picturing a previous crash. But your projected water screen is awesome - they could buy one and play footage fro…
I think the difference is that the Sydney one is very clearing telling you, the driver, to stop right now. The 11 foot 8 bridge one just looks like a generic message to all truck drivers that they should turn if they happen to be too tall. It isn't clear that it only turns on when it detects a too tall truck. If the driver of the truck thought that the bridge was too low, they wouldn't try to go under it in the first place.
Re: 11 Foot 8 – The Can-opener Bridge
#138The Sidney Harbor Tunnel had a similar problem. They came up with an elaborate but successful solution.[1] There are detectors and huge flashing warning signs that light up. Then, there's the last-chance sign. At the entrance to the tunnel, pumps force a curtain of water straight down across the entire roadway. Then a powerful laser system projects a giant octagonal red STOP sign onto the water curtain, filling the e…
Melbourne, not to be outdone by our rivals, have the Montague St bridge which is frequently doing in trucks.
Even has its own Twitter account, because of course it does:
https://twitter.com/MontagueStBridg/status/12197515386602332...
https://twitter.com/MontagueStBridg/status/12068168482782535...
https://twitter.com/MontagueStBridg/status/11919444569053306...
Re: 11 Foot 8 – The Can-opener Bridge
#139The Sidney Harbor Tunnel had a similar problem. They came up with an elaborate but successful solution.[1] There are detectors and huge flashing warning signs that light up. Then, there's the last-chance sign. At the entrance to the tunnel, pumps force a curtain of water straight down across the entire roadway. Then a powerful laser system projects a giant octagonal red STOP sign onto the water curtain, filling the e…
I thought you were joking... until I saw the video. It looks like a huge bright curtain with a 15-foot tall STOP sign unfurls in front of the driver! Whatever the cost, I'm sure it's paid for itself already.
Re: 11 Foot 8 – The Can-opener Bridge
#140What is so special about this bridge? Why do people drive under it without checking their height? You wouldn't normally think you can just drive under any bridge, would you? It doesn't even look like a very low bridge. Why do people approach it without a care in the world at full speed? My vehicle is only 2m tall and I still do take a quick look at height signs as I approach them.
A substantial number of these crashes (maybe the majority?) are rental trucks, being driven by people who aren't accustomed to operating a large vehicle. A typical driver of a car, minivan or SUV in the United States will virtually never encounter a bridge or other obstacle whose height above the road is low enough to matter to them, so most people simply never have a reason to pay attention to those height signs.
The one exception is parking garages, which often have very low roofs, where most trucks or full-size vans won't fit. But that's a totally different situation.