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Infamous 'can opener' bridge in Durham, NC, is finally being 'fixed'... 4

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Apparently, the bridge bit another one, just posted today, but occurred almost 3 weeks ago!
Again, the lights stay green, but the sign clearly flashes the warning.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
The video starts with the light red, indicating the red light was triggered to stop the vehicle and give the truck driver an opportunity to look around. The truck was in the right lane, next to the turn sign so his view of that was not blocked.

I rank this the same as people who let their truck and trailer run into the lake and sink at boat ramps.

To amplify, did this driver look at the flashing sign between the traffic lights, then look around and say "I'm the only truck here, so it cannot possibly be referring to me."? I assume he can see the light is green and is paying attention to traffic lights.
 
A more anemic bunch of warnings you couldn't come up with! Truly pathetic.
The bridge is a menace and obviously way under national norms. Because of this they should make an extra effort to warn drivers.

1) They should use a laser scanner to sweep the streets and find the approaching potential victims at a distance.

2) The warning should be nearly blinding [!]red[/!] including some RED Strobes.

[!]STOP - OVER HEIGHT VEHICLE![/!] Not some low contrast white garbage sign.

Saying they've provided adequate warning when they haven't is a poor argument.

You get more warning in a car wash that: "[blue][box][COLOR=red yellow]JIFFY WAX is being applied![/color][/blue][/box]".

Keith Cress
kcress -
 
In this mornings The News & Observer:

04DB3C1B-0159-4D33-8878-C00EB6EEB5A0_drpsge.jpg


1755FFCD-F34F-45A3-AC17-744D5F108077_w9ki2r.jpg


Good Luck,
Latexman
 
Really, just block the underpass completely. That's the only effective "warning." Sure, it means that emergency services might have extra miles to go if the grade crossings are blocked by a train, but that's the breaks to save a few ignorant drivers from hurting their vehicles.

Wasn't a red strobe light starting epileptic seizures a critical part of Andromeda Strain? Seems like a poor idea to put a someone into an epileptic fit because another person in a truck is near to them.
 
3DDave... what if we got a few dead horses and suspended them from just the right height so they would make gentle thudding sounds that would not disturb the neighbors, cause seizures, or require a local launch control centeresque command center for monitoring their functionality?
 
Ha - then the drivers of the trucks would not hear them and they would still hit the bridge guard beam.
 
Just keep the next truck roof that gets zipped off and attach it to the guard beam. That would get a truck driver's attention no problem.
 
I do like that, though I think collecting the A/C units and putting them on spikes would serve as well.
 

Truckers hit things all the time.
13 foot bridge. At least the damage as mostly to the truck; but then just chucks the debris for someone else to deal with.

10 foot 10"
(2 videos) 12 foot 6 inches

The 11 Foot 8 bridge - too funny
And yes, you cannot fix stupid.
Trucker app alerts driver before crash - does not care.
 
"...a poor argument."

This particular forum does seem to attract strongly-held opinions whose formulation is inexplicable.



 
Poor arguments are those that propose a fix, but then don't detail how that fix will flawlessly work. Given the number of other structures around the world and the number of crashes and damage from them, if there is a good fix the person with that idea will be wealthy beyond imagining. Unless the fix is far more expensive than the losses. Which is poor engineering at best.

Share those cost-effective solutions that the proposer has personally sold and has demonstrated to eliminate all such problems. No fair picking ones that are proposed to solve the problem.

Problem statement - prevent all trucks from taking a path that is open to cars.

Ready, set, GO!
 
3DDave said:
Problem statement - prevent all trucks from taking a path that is open to cars.
Click to expand...

Solution: Install bridges at a height of 11'-8" ;-)
 
That only stops their completing the path, not from taking it.

Good try.
 
That's why you have the tow truck standing by to remove the stuck truck and allow the cars to continue to flow.
 
That's 10,000 tow operators on 24 hour standby; though it is not a universal fix. Some of the collisions have destroyed the bridge. I saw one in Florida where a back-hoe clipped through all the bottom strands of the post-tension cables on one of two beams of a pedestrian walkway. The road was closed over fear of collapse for about 2 weeks until the bridge was demolished. Makes the FIU response look especially poor as the visible volume of damage was not nearly as much.

Another similar collision not only tore out the post-tension cable, but also punched out the entire web of an outer concrete beam.

The reason for all trucks is that in New York state there is a no-trucks parkway that would easily cost half a billion dollars to replace all the overpasses, apparently designed in the 1940s, and truck and semi drivers routinely ignore no-trucks signs and either get stuck, get demolished, or creatively, straddle the lanes to position under the high part of the archways.

The finders fee for avoiding a half-billion dollar fix would be a nice retirement. And would go far in keeping 36 ton trucks off of 8 ton pedestrian and light traffic bridges.

Another great source of revenue is keeping both heavy equipment such as high lifts and backhoes from being overheight (above 16'6" Federal highway limits) but also dump trucks from driving about with raised beds that seem able to reach 30 feet. Maybe all overpasses need to be 50 feet, just to be sure. In any case, the dump trucks are an especial menace as they stop the truck bed in under a second, can bring down highway spanning steel sign supports that can easily crush most cars, can punch out structural members force long term overpass closures. All because the driver has no situational awareness.

The challenge there is simple, but the circumstances are not.

The driver will cut wires and do any splicing required to stop any alarm or flashing light from distracting them on the job site where moving the truck with the bed up is necessary. I've seen it done on military equipment by enlisted workers where they "accidentally" damaged the warning beepers. Over and over again.

It can also not add any cost or have any other failure modes. Trucking firms don't want to pay for upfront or maintenance costs. It will have to last at least 30 years.

And it cannot depend on the driver to take any other action.

But it has to guarantee the bed is fully down on the stops when it is on the road, even if the PTO is engaged and the Bed-Up switch is on.

This is separate from the bridge challenge, but it would also avert injuries and deaths every year and hundreds of millions of dollars in infrastructure and personal property damage.
 
"...how that fix will [highlight #FCE94F]flawlessly[/highlight] work."

Ah, I can now see where your assumptions have gone wrong.
 
The current signage and warning solution is not flawless. It works, but not every time. Yet many feel that is not acceptable.

The only choice for improvement is to make a flawless solution. So my assumption of what is required by those railing for change is perfectly correct. The only change I'd push for is a barrier wall to protect pedestrians from ejecta; the damage to vehicles and their occupants currently doesn't bother me at all.

We know that other bridges with greater clearance than the planned alteration to this one get hit nearly as frequently; they just happen not to have their own YouTube channel to remind us of that every few months. So raising the bridge to any height is a flawed approach.

But, if one accepts failure in spending more money without benefit, then maybe that's a bad assumption.
 
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