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New highway dividers.

Started by Fatstrat, January 27, 2009, 09:21:22 PM

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patric

TULSA, OK -- Cable barriers, made to prevent accidents, didn't prevent a head on crash on a busy Tulsa highway Friday morning. The crash critically injured one driver and backed up traffic on Highway 75 for hours.

A woman was driving south and somehow managed to go airborne, then down and over the top of the cable barrier and hit an oncoming truck.

As a result, the state plans to double check the design of the barrier to make sure it's where it should be.

The accident left a minivan crushed in the front and a 30-year-old woman trapped inside seriously injured. A 50-year-old male was also injured.

"It appears she just went over the cables," said Corporal Jason Muse with Tulsa Police.

Even with higher speeds, the cable barriers usually stop cars from crossing over. In government and industry testing the barriers almost always redirect a car away from the median, but installation guidelines caution that placement is critical.

At the accident scene, the barrier was hardly damaged because the van barely touched it.

The Oklahoma Department of Transportation said it appeared the van went down the top of the cable for 70 feet before going into the northbound lanes.

The four cables stand about 32 inches high, but they're in the low spot of the median, by a road that angles up towards the median.

ODOT stands by their installation, but said they'll double check it because of the accident.

"We do go out and take a close look to see if there's anything that should be changed, and that's certainly something that we'll do here in this area, but really it's too early to speculate if anything could be changed," said Kenna Carmon with ODOT.

At the same time, the state is installing 22 more miles of cables on North Highway 75, on flatter ground, near the Tulsa and Washington county line.

The state has 600 miles of cable barriers in place, with 100 more miles planned right away. They cost one tenth as much as concrete and almost always work.

"So it has surprised us, certainly, as we've started installing cable barrier systems in Tulsa County, just the number of repairs that we're going out and making," Carmon said. "It's really eye opening to see just how many people are going into the median area and how many potential cross over accidents have been prevented."

In fact, ODOT's numbers show in the four-mile stretch of cables have been hit more than 100 times and there wasn't a single crossover until Friday morning.




"Tulsa will lay off police and firemen before we will cut back on unnecessarily wasteful streetlights."  -- March 18, 2009 TulsaNow Forum

Hoss

Quote from: patric on August 01, 2014, 11:42:35 PM
TULSA, OK -- Cable barriers, made to prevent accidents, didn't prevent a head on crash on a busy Tulsa highway Friday morning. The crash critically injured one driver and backed up traffic on Highway 75 for hours.

A woman was driving south and somehow managed to go airborne, then down and over the top of the cable barrier and hit an oncoming truck.

As a result, the state plans to double check the design of the barrier to make sure it's where it should be.

The accident left a minivan crushed in the front and a 30-year-old woman trapped inside seriously injured. A 50-year-old male was also injured.

"It appears she just went over the cables," said Corporal Jason Muse with Tulsa Police.

Even with higher speeds, the cable barriers usually stop cars from crossing over. In government and industry testing the barriers almost always redirect a car away from the median, but installation guidelines caution that placement is critical.

At the accident scene, the barrier was hardly damaged because the van barely touched it.

The Oklahoma Department of Transportation said it appeared the van went down the top of the cable for 70 feet before going into the northbound lanes.

The four cables stand about 32 inches high, but they're in the low spot of the median, by a road that angles up towards the median.

ODOT stands by their installation, but said they'll double check it because of the accident.

"We do go out and take a close look to see if there's anything that should be changed, and that's certainly something that we'll do here in this area, but really it's too early to speculate if anything could be changed," said Kenna Carmon with ODOT.

At the same time, the state is installing 22 more miles of cables on North Highway 75, on flatter ground, near the Tulsa and Washington county line.

The state has 600 miles of cable barriers in place, with 100 more miles planned right away. They cost one tenth as much as concrete and almost always work.

"So it has surprised us, certainly, as we've started installing cable barrier systems in Tulsa County, just the number of repairs that we're going out and making," Carmon said. "It's really eye opening to see just how many people are going into the median area and how many potential cross over accidents have been prevented."

In fact, ODOT's numbers show in the four-mile stretch of cables have been hit more than 100 times and there wasn't a single crossover until Friday morning.






Explains the construction I saw today on a trip I made to Caney with cones on the inside lanes near the median.  Saw plenty of the new cable barriers.

dbacksfan 2.0

In Phoenix, when they built several highways from 1998 to 2004, they initially installed these cheese graters along the center median, and then later went on to convert most all the highways to Jersey Barriers when they converted them to highways with HOV lanes. Cable barriers are okay, but they don't completely prevent crossover accidents, and sometimes are worse. Cars can go through them, get snagged and cause rollover accidents, and if a motorcyclist hits one, well just think about it. They work most of the time, but there are times that they don't. When you see a Chevy Tahoe hit one and get shot back into traffic as it rolls over, you question the logic, not that it happens often, but it does happen.

Just my $.02.

Conan71

Nothing protects people 100% of the time from their own carelessness and inattentive driving.
"It has been said that politics is the second oldest profession. I have learned that it bears a striking resemblance to the first" -Ronald Reagan

sgrizzle

Quote from: patric on August 01, 2014, 11:42:35 PM

In fact, ODOT's numbers show in the four-mile stretch of cables have been hit more than 100 times and there wasn't a single crossover until Friday morning.


Over 99% success rate? I think waxing about how bad they are is probably wasted keystrokes.

patric

Quote from: sgrizzle on August 02, 2014, 01:23:29 PM
Over 99% success rate? I think waxing about how bad they are is probably wasted keystrokes.

They are measuring success by limiting what they measure, so naturally it's an engineered outcome.
"Tulsa will lay off police and firemen before we will cut back on unnecessarily wasteful streetlights."  -- March 18, 2009 TulsaNow Forum

sgrizzle

Quote from: patric on August 02, 2014, 01:58:18 PM
They are measuring success by limiting what they measure, so naturally it's an engineered outcome.

It's a barrier with the purpose of stopping cars from going through, you measure how many times it got hit and how many cars got through. That's not cooking the books. Would you prefer we measure the fragrant scents it produces?

heironymouspasparagus

Quote from: patric on August 02, 2014, 01:58:18 PM
They are measuring success by limiting what they measure, so naturally it's an engineered contrived outcome.


Fixed it for you - it wasn't engineered, it was contrived!  If an engineer came up with the outcome, it would have had real data.
"So he brandished a gun, never shot anyone or anything right?"  --TeeDub, 17 Feb 2018.

I don't share my thoughts because I think it will change the minds of people who think differently.  I share my thoughts to show the people who already think like me that they are not alone.

Vision 2025

Having been first car behind a double-fatality, median-crossing head on accident on I-35 in Texas 27 years ago I say put them everywhere!   
Vision 2025 Program Director - know the facts, www.Vision2025.info

patric

Quote from: Vision 2025 on August 04, 2014, 10:43:19 AM
Having been first car behind a double-fatality, median-crossing head on accident on I-35 in Texas 27 years ago I say put them everywhere!   

If you had the choice, would you prefer a concrete Jersey Barrier that deflects the energy of a crashing vehicle, or cables that abruptly snag that force?
When the ultimate goal is to save lives (not just those in opposing traffic), which device is more likely to accomplish that?
"Tulsa will lay off police and firemen before we will cut back on unnecessarily wasteful streetlights."  -- March 18, 2009 TulsaNow Forum

Conan71

Quote from: patric on August 04, 2014, 11:00:46 AM
If you had the choice, would you prefer a concrete Jersey Barrier that deflects the energy of a crashing vehicle, or cables that abruptly snag that force?
When the ultimate goal is to save lives (not just those in opposing traffic), which device is more likely to accomplish that?

The cables will dissipate more energy with a more direct shot than a Jersey barrier will.  Jersey barriers can also flip vehicles with a glancing shot.

Best idea is put your phone down and drive so you don't need to worry about the barriers.
"It has been said that politics is the second oldest profession. I have learned that it bears a striking resemblance to the first" -Ronald Reagan

heironymouspasparagus

Quote from: Conan71 on August 04, 2014, 11:54:47 AM
The cables will dissipate more energy with a more direct shot than a Jersey barrier will.  Jersey barriers can also flip vehicles with a glancing shot.

Best idea is put your phone down and drive so you don't need to worry about the barriers.


I second the motion!   

Why doesn't Oklahoma have a law about that....   oh, yeah...for a moment, I almost forgot....!!

"So he brandished a gun, never shot anyone or anything right?"  --TeeDub, 17 Feb 2018.

I don't share my thoughts because I think it will change the minds of people who think differently.  I share my thoughts to show the people who already think like me that they are not alone.

sgrizzle

Quote from: patric on August 04, 2014, 11:00:46 AM
If you had the choice, would you prefer a concrete Jersey Barrier that deflects the energy of a crashing vehicle, or cables that abruptly snag that force?
When the ultimate goal is to save lives (not just those in opposing traffic), which device is more likely to accomplish that?

You know they're not made of pillows, right?

They "deflect" that energy right back into the person who hits it, resulting in higher fatalities and chance of injury.

Quote
There are three basic categories of median barriers: rigid barrier systems, semi-rigid barrier systems, and flexible barrier systems.

Rigid Barriers: Concrete barriers are the most common type of rigid median barrier in use today. While the initial cost of installation can be relatively high, concrete barriers are known for their relatively low life-cycle cost, effective safety performance, and their relatively maintenance-free characteristics. One drawback is that crashes associated with rigid barriers may result in more severe injuries because, relative to other barrier systems, a rigid system absorbs the least energy in a crash. Nevertheless, concrete barriers have proven to be very effective at mitigating median crossover collisions, especially in locations with high traffic volumes and high speeds. These barrier systems have proven to be highly effective in locations with high traffic volumes and high speeds. Concrete barrier systems are also very effective in places with heavy truck traffic, and in areas where sufficient median widths to accommodate other barrier systems are not available.

Semi-Rigid Barriers: Commonly referred to as guardrail or guiderail, semi-rigid barriers typically consist of connected segments of metal railing supported by posts and blocks. The semi-rigid barrier system is most suitable for use in traversable medians having no or little change in grade and cross slope. In comparison to rigid barriers, semi-rigid barriers can be less costly, but can be more difficult to install in locations with slope and poor soil conditions. Additionally, the need for repair following impact can drive up life-cycle cost. Guardrail systems are designed to absorb energy during a crash, and the entire assembly is designed to move or deflect during an impact.

Cable Barriers: A typical cable barrier consists of multiple steel cables that are connected to a series of posts. These systems are considered the most versatile and forgiving barrier systems available for reducing the severity of median crossover crashes. Cable median barriers minimize the forces on the vehicle and its occupants and absorb most of the energy of a crash. In comparison to rigid and semi-rigid barriers systems, cable barrier systems generally have a lower installation cost. Like guardrails, however, they typically require maintenance after a crash, and therefore can have a higher life cycle cost.

Vision 2025

Quote from: patric on August 04, 2014, 11:00:46 AM
If you had the choice, would you prefer a concrete Jersey Barrier that deflects the energy of a crashing vehicle, or cables that abruptly snag that force?
When the ultimate goal is to save lives (not just those in opposing traffic), which device is more likely to accomplish that?
I would rather see the Jersey2 but if the choice is cable or nothing I'll take the cable every time.
Vision 2025 Program Director - know the facts, www.Vision2025.info

patric

Quote from: Conan71 on August 04, 2014, 11:54:47 AM
The cables will dissipate more energy with a more direct shot than a Jersey barrier will.  Jersey barriers can also flip vehicles with a glancing shot.

It seems possible, but all of the accidents I have seen involving cables involve glancing impacts and off-center contact.  Ive never seen one hit at a direct right-angle.
A couple of years ago, the Feds started clamping down on concrete barriers built shorter than spec, where vehicles did roll over them.  You likely notice newer ones are much taller.

"Tulsa will lay off police and firemen before we will cut back on unnecessarily wasteful streetlights."  -- March 18, 2009 TulsaNow Forum