Author Topic: How would you use electronics to solve the 11' 8" bridge problem  (Read 12566 times)

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Offline Mr. Scram

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #25 on: January 07, 2018, 11:32:49 pm »
Sometimes the simplest solution is the best. Increase the height of the bridge, lower the height of the road or a combination of both. The rest are just engineering problems. They raise bridges many times larger than these all the time, so it's basically a solved problem.

I'm not buying the sewer pipe story either. There's plenty of other places to put those pipes if you want to and it's actually not uncommon for sewage pipes to dip in a few places. If you somehow concluded there absolutely is no room for them underneath the overpass, there's remote controlled drilling. You can go right under the embankment, allowing the underpass to be as deep as you'd want.

At this point it's just shifting the cost of fixing the problem upon the insurances of unlucky drivers. When there's over a 100 crashes, it's looking like the road authority neglecting its duties more and more.
 
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Offline IanB

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #26 on: January 07, 2018, 11:34:16 pm »
People love to hate on other people in situations like these, but if behaviour is this consistent, blaming the people isn't going to work. It's like those perfect parent who would never leave their children in the car. The truth is they would. It's a flaw in human behaviour, not just shoddy parenting.

That's maybe the most freighting thing. You live your life the way everyone expects you to and are a responsible adult, until you suddenly aren't any more and you haven't even consciously made the wrong choice. It could happen to pretty much anyone.

Bad behavior can be fixed by training in the human animal, just like any animal.

Only yesterday someone ran a red light and turned across in front of me a full 2-3 seconds after I had a green light to proceed. If they were guaranteed a ticket, a fine, and points on their license every time they did that, they certainly would stop doing it.
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Offline IanB

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #27 on: January 07, 2018, 11:36:05 pm »
At this point it's just shifting the cost of fixing the problem upon the insurances of unlucky incompetent drivers.

There, fixed that for you. Also, if you claim on insurance for an at-fault accident, your insurance premium will go up a lot next renewal. Insurance companies don't bear the cost, you do.
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Offline NiHaoMike

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #28 on: January 07, 2018, 11:39:13 pm »
People love to hate on other people in situations like these, but if behaviour is this consistent, blaming the people isn't going to work. It's like those perfect parent who would never leave their children in the car. The truth is they would. It's a flaw in human behaviour, not just shoddy parenting.

That's maybe the most freighting thing. You live your life the way everyone expects you to and are a responsible adult, until you suddenly aren't any more and you haven't even consciously made the wrong choice. It could happen to pretty much anyone.
I'd imagine a very large percentage of the accidents with that bridge were by drivers who have driven their car under it hundreds or even thousands of times before. If they only drive a truck occasionally, it's easy to forget about the height limitations and "take the route they have always taken". Something similar also happens with roof racks.
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Offline Mr. Scram

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #29 on: January 07, 2018, 11:39:29 pm »
Bad behavior can be fixed by training in the human animal, just like any animal.

Only yesterday someone ran a red light and turned across in front of me a full 2-3 seconds after I had a green light to proceed. If they were guaranteed a ticket, a fine, and points on their license every time they did that, they certainly would stop doing it.
Not all bad behaviour can be "fixed". The impulse is to fine and punish, but in this case that's obviously not going to make a difference. Even at the cost of writing off a truck and possibly losing your job people still manage to do it in droves.

Aerospace is a great example of how to prevent user error. Rather than projecting all sorts of moral viewpoints on the matter, they take a practical "if it works" approach. You can't afford much else when people die if you get it wrong.
 
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Offline Mr. Scram

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #30 on: January 07, 2018, 11:49:01 pm »
There, fixed that for you. Also, if you claim on insurance for an at-fault accident, your insurance premium will go up a lot next renewal. Insurance companies don't bear the cost, you do.
I'm not sure why you ignore everything in my post just to say "nu-uh!". I've addressed this as just blaming the drivers for incompetence is ridiculously oversimplifying things. It's way too easy to just attribute it to incompetence. Many books have been written on how humans can fail at performing what seemingly are the simplest tasks. These people are convinced they would never get it wrong either, until they did. That's why I added the example of children being left in the car. You'd think responsible parents would get a very basic thing right if it meant the life of their child if they got it wrong. Yet reality shows us something different. These aren't neglectful parents either, the vast majority are proven to be loving, caring and otherwise responsible parents.

Obviously, insurances paying the cost means the insured paying the cost, but I didn't think anyone needed that to be spelled out and it doesn't change the point being made. The road authority, city or whoever needs to pay to make things right is shifting the cost elsewhere. Obviously, that's paid by society too, but that too isn't the point.
 

Offline donotdespisethesnake

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #31 on: January 07, 2018, 11:52:51 pm »
I would put a curtain or flap below the bridge which makes it look for too low for a regular truck. A height sensor could open the flap if the vehicle height is ok.
Bob
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Offline Someone

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #32 on: January 08, 2018, 12:00:08 am »
11 foot plus? There are worse examples around the world:
http://www.abc.net.au/news/2016-05-19/montague-st-bridge-to-get-new-gantry-to-try-prevent-crashes/7430400
Along with more excuses about not being able to lower the road which can be solved if the will is there.

I would put a curtain or flap below the bridge which makes it look for too low for a regular truck. A height sensor could open the flap if the vehicle height is ok.
Thats been tried many times before, either its non-destructive and some of the drivers will ignore it and continue on or its destructive (solid beam) and the tall vehicles get caught there instead.
 

Offline Maxlor

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #33 on: January 08, 2018, 12:31:32 am »
I'd say their current solution is good enough. It'll keep 99.5% of drivers from damaging their trucks. The cost to stop the last 0.5% – eh, not worth it. We're not talking about loss of life here, it isn't that important to prevent every single crash. (The numbers are guesses: as per the website, there seem to be around 15 crashes per year. I'd conservatively guess that at least 3000 trucks run under it per year in total.)
 
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Offline T3sl4co1l

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #34 on: January 08, 2018, 01:00:19 am »
This thread is a great example of human thought process (in two ways):

1. Regarding the drivers. People assume that these drivers are somehow paying attention, and [consciously] at fault.

You can't fix stupid.

People are stupid.  Seriously stupid.  Blind walking off a cliff stupid.

Not nearly all of them, no, not by any means.

Consider the evidence.  The authorities have done more than due diligence in marking this intersection.  The vast majority of drivers obey these signs.

We aren't dealing with normal people here.  We cannot apply normal psychology.  Or logic even.

Consider this when making your judgements. :)


2. Regarding the posters in this thread.

This is an excellent case study in the availability and use of information (evidence) and knowledge.

It's an interesting design problem, because most people have an intuitive grasp of mechanics.  Small space, truck cannot fit.  Simple as that!

Typical solutions mentioned:
- Raise the bridge
- Lower the road
- Add more barriers
- Add immediate punishments

Most of the above judgements have not been corrected when new information is provided; instead, they are met with incredulity, as if such a simple solution could ever be contradicted, no matter the weight of evidence against it!

The last option is the most disturbing.  One poster suggested adding booby traps to the intersection!  If that doesn't scare the shit out of you, more than human zombies driving trucks does -- I don't know what can!

The second-to-last option is the only feasible alternative, but at great expense.  For example, a hydraulic ramp could be added, to divert trucks at the last minute, preventing damage to the bridge and minimizing damage to the vehicle. 

Ultimately, it all comes down to two things:

1. The situation is always more complex than it looks at first glance. Knee-jerk reactions are just that: being a jerk!  Take a moment to consider why something might be the way it is, and reflect upon that.

Indeed, this applies recursively; the complexity is always more complex.  It's just that, most times, there's a convenient threshold beyond which we needn't consider further complexities.  This is what engineering is all about (and physics, except for the deepest unsolved problems that cannot be reduced this way: tightly interactive condensed matter and QCD, for two examples).

2. Money.  It's all about money, baby.

This intersection is apparently a modestly important transportation route, so adding barriers would be counterproductive, and that counterproductivity is directly measurable in the dollar value of that transportation (versus if there are any alternative routes, and whatever knock-on effects that might further have).

The cost to all involved in a collision is directly measurable.  One totaled truck, its cargo (which might not be totaled, but delayed to the destination at least), the emergency response, whatever cleanup and repair is needed, a few other inconvenienced (delayed or rerouted) vehicles backed up behind the accident; and not much more.  Likely traffic fines and insurance cover the immediate costs, and everything else (like the inconvenienced travelers) is a wash-out.

Moreover, the rate is directly measurable.  If this happens a few times a year, then there you go.

That cost is your baseline to judge alternatives on.  Nothing more.  If it costs the rail company more than so-and-so (amortized over some years) to change the bridge, it's simply not worth it -- it doesn't affect enough people, business and such to change.  Does this bother you?  Should it?  It might look like a suboptimal solution, but on closer inspection, it's very nearly the non-zero ground state it should be! :)

And this has been your lesson in holistic engineering for the day.

Cheers,
Tim
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Offline drussell

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #35 on: January 08, 2018, 01:03:00 am »
(The numbers are guesses: as per the website, there seem to be around 15 crashes per year. I'd conservatively guess that at least 3000 trucks run under it per year in total.)

I would think it is more like 3000 trucks per week.
 

Online Brumby

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #36 on: January 08, 2018, 02:15:49 am »
The "Overheight Must Turn" sign is too high - and not very clear.  It may be obvious if you spend a few seconds thinking about it, but they are in a vehicle that is going to travel a long distance in those few seconds - and they will be doing other things like seeing if there are other cars coming while they run the red light.

I would make that sign larger and put it lower down - with a message like "Vehicle too high. Turn or CRASH!"

Put billboards either side with a panel across the bridge joining them and get a graphic artist to put together a design showing big teeth (or something more creative) with a message saying: "Welcome to our truck eating bridge".  Make it good enough to be a tourist attraction and find its way onto social media.  Make it bright and unique, to attract attention and leave a lasting impression - so when any truck driver approaches the intersection and sees the display, it might just twig before they go crunch.



But I do like the water curtain.   :-+
 

Online Ian.M

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #37 on: January 08, 2018, 02:18:43 am »
Large hard rubber balls hung on chains 11' 6" above the road surface 100m before the bridge on the road under it  (half the road width, with a traffic island so it doesn't affect trucks turning away from the bridge) + another set in line with the sidewalk right across the bridge side of the junction to catch those turning off the cross street.

It wont stop *ALL* the idiots, but if it wakes up 2/3 of them before they hit the hard barrier, it would be worth it for the reduced disruption and vehicle damage.
 

Offline timb

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #38 on: January 08, 2018, 02:19:59 am »
People love to hate on other people in situations like these, but if behaviour is this consistent, blaming the people isn't going to work. It's like those perfect parent who would never leave their children in the car. The truth is they would. It's a flaw in human behaviour, not just shoddy parenting.

That's maybe the most freighting thing. You live your life the way everyone expects you to and are a responsible adult, until you suddenly aren't any more and you haven't even consciously made the wrong choice. It could happen to pretty much anyone.
I'd imagine a very large percentage of the accidents with that bridge were by drivers who have driven their car under it hundreds or even thousands of times before. If they only drive a truck occasionally, it's easy to forget about the height limitations and "take the route they have always taken". Something similar also happens with roof racks.

I think you hit the nail (or truck) on the head. If you watch the compilation video of all 126 crashes, you’ll notice a pattern to the crashes. The vast majority of them are rental trucks (Penske, Enterprise, etc.) and RVs. You’ll notice only one or two tractor trailers (18-wheelers).

These are all large vehicles, however the difference is in the driver. Tractor trailers require a commercial drivers license. The large rental box trucks don’t. Part of training for a CDL is being intimately aware of how high your trailer is. Though that still doesn’t mean CDL drivers don’t screw up!

I’m from Hampton Roads VA, which has numerous bridge tunnels due to all the shipyards and ports. Some of these tunnels would lower about 12” in height over the first 200ft, so you’d occasionally run into situations where tractor trailer drivers would get lodged inside the tunnel! They’d have to deflate the tires and back them out. This despite automated warnings that would flash lights and direct loud warning sirens toward the truck, telling them to pull off into a manned inspection station. Most of these drivers would be fined thousands of dollars and potentially lose their CDL. (And that’s what keeps most CDL drivers from screwing up like this; losing their license means losing their livelihood.)

Anyway, I used to drive a flatbed about the size of the truck in the OP’s video. I delivered wooden shipping pallets and the truck would be loaded with stacks of them 40 high. However, because the overall height could vary depending on the type of pallet loaded, I kept a tape measurer on me and I would always check my height before pulling out of the plant.

As for this 11’8” bridge, I think the solution they’re currently using  (height sensors to turn the light red and a sacrificial beam) is the best they can do. Even spike strips that pop up wouldn’t help, based on the speed some of the trucks were going when they hit the bridge. Though, perhaps a large speed bump before the intersection might help to force the drivers to slow down.
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Offline TerraHertz

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #39 on: January 08, 2018, 03:06:28 am »
As others have said, you cannot fix stupid.

There's an even more extreme low bridge example near where I live. There is no straight-through street, ie every vehicle trying to go under the rail bridge has to turn to enter the underpass, so there are never any high-speed approaches. Also the clearance is only 2.4m, so it looks very low. The huge protective steel beams are brightly painted in stripey yellow and black, with sacrificial replaceable impact buffers, and clearly marked with the 2.4m height.

People still drive trucks into it. Plenty of dings and marks on the beam, and it's frequent enough that I've seen a wrecked truck there, when I just happened to drive by.

https://www.google.com.au/maps/place/South+Terrace,+Bankstown+NSW+2200/@-33.9181519,151.0414493,17z/data=!3m1!4b1!4m5!3m4!1s0x6b12bc0703611445:0xc11f4499e161649a!8m2!3d-33.9181564!4d151.0436433?hl=en

There's actually a large stormwater canal passing under the rail line directly under the road surface there, so there's nothing that can be done about the clearance.

The only way I can think of to 'electronically improve' the situation, would be to add large speakers to play a laughter and applause sound track, starting just before an overheight vehicle impacts, and running for maybe a minute afterwards. Strictly for the amusement of bystanders.
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Online Ian.M

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #40 on: January 08, 2018, 03:14:10 am »
Add some more cameras to get good video of the driver reactions,  arrest them all for reckless driving, and put their mug shots and the video clips on the local TV news.
 

Offline Cubdriver

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #41 on: January 08, 2018, 04:10:29 am »
Low tech solution: a steel beam hung (by chains from poles so it's still free to move) an inch or two lower than the bridge a few tens of feet before the bridge. Colliding with it will make a loud noise, but with far less damage than colliding with the bridge itself.

Or a sign...



I'm not sure where this is, I first saw it years ago.  It's simple, and (I'd think, at least) clear.  I'm sure morons would still scalp themselves on the bridge, but perhaps a few would be warned off...

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Offline Mr. Scram

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #42 on: January 08, 2018, 04:16:07 am »
It's funny, yet unsurprising how people insist on the reason being "stupid", while the statistics and psychology tell another story. Obviously, claiming moral superiority feels good, and people love pointing fingers and shake fists, but that doesn't mean it's right. It's a lesson aviation learnt a long time ago, but surprisingly hasn't quite trickled down to driving or the general public. You could put the death penalty on hitting that bridge and it's unlikely the numbers would be much different.

https://www.parents.com/baby/safety/car/youd-never-forget-your-child-in-the-car-right/
https://en.wikipedia.org/wiki/Human_factors
https://en.wikipedia.org/wiki/Pilot_error
 

Online Brumby

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #43 on: January 08, 2018, 04:17:14 am »
As others have said, you cannot fix stupid.

There's an even more extreme low bridge example near where I live. There is no straight-through street, ie every vehicle trying to go under the rail bridge has to turn to enter the underpass, so there are never any high-speed approaches. Also the clearance is only 2.4m, so it looks very low. The huge protective steel beams are brightly painted in stripey yellow and black, with sacrificial replaceable impact buffers, and clearly marked with the 2.4m height.

People still drive trucks into it. Plenty of dings and marks on the beam, and it's frequent enough that I've seen a wrecked truck there, when I just happened to drive by.

https://www.google.com.au/maps/place/South+Terrace,+Bankstown+NSW+2200/@-33.9181519,151.0414493,17z/data=!3m1!4b1!4m5!3m4!1s0x6b12bc0703611445:0xc11f4499e161649a!8m2!3d-33.9181564!4d151.0436433?hl=en
I driven through there.  It is imposing, even driving a regular car under it.


Quote
The only way I can think of to 'electronically improve' the situation, would be to add large speakers to play a laughter and applause sound track, starting just before an overheight vehicle impacts, and running for maybe a minute afterwards. Strictly for the amusement of bystanders.

I like the idea - but I'd change it slightly....

As the overheight truck approaches, start a drum roll.  If they turn off, then finish with a cheer and appreciative applause.  If they don't, then have some excited anticipation shouts of "Look! Look! Here's another one!", a cymbal crash timed to match their impact - and then have the raucous laughter and over the top applause.
 

Online Brumby

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #44 on: January 08, 2018, 04:23:32 am »
I'd imagine a very large percentage of the accidents with that bridge were by drivers who have driven their car under it hundreds or even thousands of times before. If they only drive a truck occasionally, it's easy to forget about the height limitations and "take the route they have always taken". Something similar also happens with roof racks.

I think you hit the nail (or truck) on the head. If you watch the compilation video of all 126 crashes, you’ll notice a pattern to the crashes. The vast majority of them are rental trucks (Penske, Enterprise, etc.) and RVs. You’ll notice only one or two tractor trailers (18-wheelers).

These are all large vehicles, however the difference is in the driver.

I concur.  I've driven a couple of larger vehicles - but these occasions have been few and far between.  I have been driving smaller vehicles (up to the size of a Tarago) for years - but I have to consciously remind myself of the height of the truck - and more importantly the height above my eye line.  It's not a foot any more - it can be four feet or even more and tree branches that were never a problem, suddenly present themselves as real obstacles.

I've never had a problem or impact with the height - but I did have a near miss once when backing a truck with a high pantech body.  I was looking along the vehicle through the rear view mirror and just missed a first storey cantilevered office by two inches.  I should have looked up as well...  :-[
« Last Edit: January 08, 2018, 04:28:51 am by Brumby »
 

Online SeanB

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #45 on: January 08, 2018, 09:11:45 am »
By me there is also a low pair of bridges. Lower the road under them not easy, as they are on a decline at the bottom, and the approach would be steeper then. Raise the top section very expensive, as you would have to raise 6km of race course grass as well, along with all the side parts. So what the Metro did was put warning signs each end of the 2 bridges, and at the side by the hill put a large traffic circle, so that vehicles are forced to slow down.

Did reduce the accident rate slightly, but stupid is still there, as evidenced by the numerous times speeders have gone airborne over the traffic island, despite the nice rockery there to arrest them, and the residents of the one sectional complex on the one side getting tired or rebuilding the wall, so they have permanent concrete Jersey barrier blocks on the pavement now on that corner. Had a municipal bus take a short cut under the one and get wedged, they had to remove it by deflating the tyres and dragging it back, and the other side a furniture truck tried to take a short cut, and got the van section torn off the chassis. One more from years ago my father was involved with as the manager of the truck, but that was grisly.
 

Offline Mr. Scram

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #46 on: January 08, 2018, 09:19:23 am »
I concur.  I've driven a couple of larger vehicles - but these occasions have been few and far between.  I have been driving smaller vehicles (up to the size of a Tarago) for years - but I have to consciously remind myself of the height of the truck - and more importantly the height above my eye line.  It's not a foot any more - it can be four feet or even more and tree branches that were never a problem, suddenly present themselves as real obstacles.

I've never had a problem or impact with the height - but I did have a near miss once when backing a truck with a high pantech body.  I was looking along the vehicle through the rear view mirror and just missed a first storey cantilevered office by two inches.  I should have looked up as well...  :-[
You criminal scum. You should be locked up and your pictures should be spread for everyone to ridicule! Absolute reckless driving.

Or so some would say.
 

Online Jeroen3

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #47 on: January 08, 2018, 12:35:29 pm »
Even spike strips that pop up wouldn’t help, based on the speed some of the trucks were going when they hit the bridge.
Flat tires reduce the height.
 

Offline W2NAP

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #48 on: January 08, 2018, 01:09:52 pm »
Even spike strips that pop up wouldn’t help, based on the speed some of the trucks were going when they hit the bridge.
Flat tires reduce the height.

trying to pop the tires of a CMV when in motion is not a good idea... they are not like car tires only holding 40lbs of air, they usually hold 90 to 110lbs of air. and sudden loss of air in the steer tires when in motion is bad juju.

here is video of a steer tire blowout while in motion.

 

Offline tooki

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Re: How would you use electronics to solve the 11' 8" bridge problem
« Reply #49 on: January 08, 2018, 03:49:24 pm »
Sometimes the simplest solution is the best. Increase the height of the bridge, lower the height of the road or a combination of both. The rest are just engineering problems. They raise bridges many times larger than these all the time, so it's basically a solved problem.

I'm not buying the sewer pipe story either. There's plenty of other places to put those pipes if you want to and it's actually not uncommon for sewage pipes to dip in a few places. If you somehow concluded there absolutely is no room for them underneath the overpass, there's remote controlled drilling. You can go right under the embankment, allowing the underpass to be as deep as you'd want.
If it were simple, they’d have done this. Raising a railroad track? Forget it. You can’t just bump it up two feet for a quarter-mile or something, because those big freight trains cannot handle steep inclines, especially not somewhere where trains stop (which they do around there). If it were a street bridge it’d be easy to raise, but this is freight rail. You’d probably have to raise the rail bed for miles on either side, which would be enormously expensive (and possibly cause other problems).

I’d be more curious about the pipes, since I would assume something could be done. But if they haven’t done it after a century of accidents, there’s damned well a reason for it.

At this point it's just shifting the cost of fixing the problem upon the insurances of unlucky drivers. When there's over a 100 crashes, it's looking like the road authority neglecting its duties more and more.
The city is under no obligation for every road to be passable by every vehicle. This hazard is marked for blocks in advance, overheight sensors, etc. They’ve done more than enough to warn drivers of the hazard. At some point, a driver has to take responsibility!!



It is a main road leading to the port.  That's not a practical solution.
Main road? Port? Whaaa? It’s actually a small surface road in an old downtown, in a city that’s about 150 miles inland. Map link below.


Low tech solution: a steel beam hung (by chains from poles so it's still free to move) an inch or two lower than the bridge a few tens of feet before the bridge. Colliding with it will make a loud noise, but with far less damage than colliding with the bridge itself.
Large hard rubber balls hung on chains 11' 6" above the road surface 100m before the bridge on the road under it  (half the road width, with a traffic island so it doesn't affect trucks turning away from the bridge) + another set in line with the sidewalk right across the bridge side of the junction to catch those turning off the cross street.

Can’t do that, because it’s an intersection, and the cross street does not have height restrictions. Literally anywhere earlier than where it is would block trucks from places they have to go. There’s no room widen the road to make an island or a separate turning lane, it’s an old downtown, with the street flanked by buildings.

Here’s the location: https://goo.gl/maps/RsFdX3dwLCF2

The "Overheight Must Turn" sign is too high - and not very clear.  It may be obvious if you spend a few seconds thinking about it, but they are in a vehicle that is going to travel a long distance in those few seconds - and they will be doing other things like seeing if there are other cars coming while they run the red light.
The sensor for the sign is quite far back, and turns the light to red with ample time to stop when an overheight vehicle approaches. (In USA, it’s legal to turn right on red, so the red light doesn’t stop the truck from turning to safety.) The video in the OP shows clearly that the driver had a red light for at least 5 seconds before entering the intersection. It’s a downtown surface road with a commensurately low speed limit, so there’s plenty of stopping distance.


 


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