AARoads Forum

National Boards => General Highway Talk => Topic started by: roadman65 on February 23, 2015, 11:48:42 AM

Title: Cable guard rails
Post by: roadman65 on February 23, 2015, 11:48:42 AM
When I lived in New Jersey growing up as a kid I remember New Jersey's highways had cables attached to white posts instead of today's W guard rails.  They were all replaced slowly all throughout the 1980's so that by 1990 they were all gone, but were mostly all there in the 1970's.  It was pretty much concrete highways with those white post guide rails all growing up for me.  I think it was when NJDOT paved over the original concrete pavements when they included guardrail replacement.

I also remember Pennsylvania having them as well and parts of New York State in addition to their box rails but not white painted like NJ had but bare medal.  The western part of the PA Turnpike used them west of Breezewood and the rest of PA highways including US 22.  Now they were not like NJDOT and the rest of the Garden State removing them all over time, but they did replace many of them though.  New York still has them as I saw back in 12, but in remote places along their interstates.

Florida now has them on the FL 528 in the median of the freeway from FL 417 to FL  520 as the deterrence to prevent median crossovers as other Florida Freeways use the W guard rail to stop wayward vehicle crossovers.  The FL 528 cables are attached to skinny mono tube posts unpainted similar to PA's.

What areas still use these cable stayed stoppers to this day other then Florida's Beachline and why were they replaced in New Jersey and parts of PA?  I know that my dad told me the nature of those cables as they were flexible which slowed down any object that breached them over the fixed medal rails which are not which I can understand, but why the switch to fixed medal and enough for NJDOT to rid themselves of all of their cable stayed devices?
Title: Re: Cable guard rails
Post by: freebrickproductions on February 23, 2015, 11:57:20 AM
We have them in the median of the interstates in Alabama.
Title: Re: Cable guard rails
Post by: Big John on February 23, 2015, 12:04:50 PM
Many states have put them in the median now as a lower-cost alternative to try to prevent a wayward vehicle from entering oncoming traffic.  Applies to wide depressed medians only. Placement is usually on one side of traffic rather than in the ditch.
Title: Re: Cable guard rails
Post by: WillWeaverRVA on February 23, 2015, 12:33:41 PM
Virginia has these in places, particularly along the stretch of I-95 between Fredericksburg and Ashland, although recently VDOT has been replacing them with regular guardrails as traffic increases.
Title: Re: Cable guard rails
Post by: jeffandnicole on February 23, 2015, 12:40:34 PM
PA still has them on I-95 between Delaware & Chester.  (I think maybe near the airport as well)

I remember reading NJ was going to add cable barriers to medians that didn't have any protection. While their cost is cheaper than metal guiderail, once they're hit they aren't very effective until they're fixed, whereas a damaged guiderail may not look pretty but still retains most of its effectiveness.  After some experiences with a few installed cable barriers, NJ decided to use metal guiderail instead.  Depending on the road, they've used W or Thrie.
Title: Re: Cable guard rails
Post by: slorydn1 on February 23, 2015, 01:07:00 PM
We have the cable barriers on both the US-70 freeway between Dover and the Freedom Memorial Bridge in New Bern, as well as on the new US-17 freeway alignment west of New Bern. The barrier on 70 has only been there for about 10 years or so, before that there was nothing but the wide median and luck.

Title: Re: Cable guard rails
Post by: kphoger on February 23, 2015, 02:27:41 PM
Quote from: Big John on February 23, 2015, 12:04:50 PM
Many states have put them in the median now as a lower-cost alternative to try to prevent a wayward vehicle from entering oncoming traffic.  Applies to wide depressed medians only. Placement is usually on one side of traffic rather than in the ditch.

This doesn't apply to wide, depressed medians only. Take a look at GSV for I-44 several miles south of Walters, Okla., for an extreme example.
Title: Re: Cable guard rails
Post by: hbelkins on February 23, 2015, 02:33:08 PM
I remember the old cables with white posts, or white posts only, in Kentucky. Very, very, very few examples are left.

Kentucky is installing cable barriers in the medians of interstates and freeways on an increasing basis.
Title: Re: Cable guard rails
Post by: briantroutman on February 23, 2015, 02:33:55 PM
You can learn all about the compromises between various barrier types (strong vs. weak-post, rigid vs. flexible) by watching this FHWA video (https://archive.org/details/gov.dot.fhwa.ttp.vh-48c). If you want to jump right to the particulars of cable barriers, skip ahead to the 35-minute mark.

According to that video, there are relatively few places where cable barriers are appropriate. Unlike the typical W-beam guardrail setup, cable barriers are very flexible. By design, they deflect as much as 17 feet when hit, so they should only be used in places where there's a clear recovery area that extends more than 17 feet beyond the barrier. And since cable barriers are basically sacrificial (even one light hit, and the entire system needs to be replaced) they're ideally placed at least 20 feet from the edge of roadway.

In the past in Pennsylvania, I've seen cable barriers used on rural secondary state routes with narrow gravel shoulders and ditches, trees or other obstructions immediately behind (like this (https://goo.gl/maps/Nffxh))–nearly the antithesis of FHWA's recommended scenario.

Cable barriers are the best for driver and car because the gradual deflection helps to absorb impact energy, reducing damage on both the vehicle and its occupants, but if a wide clear zone can't be created behind the barrier, or if the DOT can't maintain a cable barrier that's frequently hit, that would nullify the benefits.
Title: Re: Cable guard rails
Post by: jeffandnicole on February 23, 2015, 02:44:44 PM
Quote from: briantroutman on February 23, 2015, 02:33:55 PM
You can learn all about the compromises between various barrier types (strong vs. weak-post, rigid vs. flexible) by watching this FHWA video (http://youtu.be/usUYVTZtl9c). If you want to jump right to the particulars of cable barriers, skip ahead to the 35-minute mark.

According to that video, there are relatively few places where cable barriers are appropriate. Unlike the typical W-beam guardrail setup, cable barriers are very flexible. By design, they deflect as much as 17 feet when hit, so they should only be used in places where there's a clear recovery area that extends more than 17 feet beyond the barrier. And since cable barriers are basically sacrificial (even one light hit, and the entire system needs to be replaced) they're ideally placed at least 20 feet from the edge of roadway.

In the past in Pennsylvania, I've seen cable barriers used on rural secondary state routes with narrow gravel shoulders and ditches, trees or other obstructions immediately behind (like this (https://goo.gl/maps/Nffxh))–nearly the antithesis of FHWA's recommended scenario.

Cable barriers are the best for driver and car because the gradual deflection helps to absorb impact energy, reducing damage on both the vehicle and its occupants, but if a wide clear zone can't be created behind the barrier, or if the DOT can't maintain a cable barrier that's frequently hit, that would nullify the benefits.

So you mean cable barrier set just off the pavement along I-95 in PA like this: http://goo.gl/maps/gzaAB isn't acceptable?  17 feet would put a car coming from 95 North into the center lane of 95 South!
Title: Re: Cable guard rails
Post by: Caboosey on February 23, 2015, 03:15:30 PM
I have been trying to get Caltrans (California DOT) to install one on Southbound Hwy 101 between Exit 191B and 191A in Pismo Beach, CA. The City of Pismo Beach want it, but Caltrans wont go for it. People can easily go off the road and hit cars on Price street / Hwy 1 head on. Someone already went off the road, Hwy 101 southbound, there once and killed two pedestrians on Price Street / Hwy 1 walking on sidewalk.

Location: https://www.google.com/maps/@35.1485899,-120.6492576,670m/data=!3m1!1e3 (https://www.google.com/maps/@35.1485899,-120.6492576,670m/data=!3m1!1e3)
Streetview: https://www.google.com/maps/@35.148824,-120.649219,3a,75y,124.94h,79.93t/data=!3m4!1e1!3m2!1ssSpSPn8vXVWAjpYDMA70qg!2e0 (https://www.google.com/maps/@35.148824,-120.649219,3a,75y,124.94h,79.93t/data=!3m4!1e1!3m2!1ssSpSPn8vXVWAjpYDMA70qg!2e0)

News article: http://www.sanluisobispo.com/2010/10/16/1330911_pismo-fatality-freeway-pedestrian.html?rh=1 (http://www.sanluisobispo.com/2010/10/16/1330911_pismo-fatality-freeway-pedestrian.html?rh=1)

Caltrans 2010 design standards for Cable guard rails: http://www.dot.ca.gov/hq/esc/oe/project_plans/highway_plans/stdplans_US-customary-units_10/viewable_pdf/b11-47.pdf (http://www.dot.ca.gov/hq/esc/oe/project_plans/highway_plans/stdplans_US-customary-units_10/viewable_pdf/b11-47.pdf)
Title: Re: Cable guard rails
Post by: cl94 on February 23, 2015, 06:23:15 PM
New York still uses them, although they're mainly found on freeways. Typically placed in depressed medians or next to a gradual slope.

High-tension systems (what NY currently uses, for example) have a deflection of ~4 feet when hit by a passenger car and will remain effective outside of the crash area, even if hit. Exerts less force on vehicles than typical barriers.
Title: Re: Cable guard rails
Post by: Brian556 on February 23, 2015, 07:04:08 PM
US 77 in Oklahoma still has some that are very old:

https://maps.google.com/maps?ll=34.429505,-97.143864&spn=0.000018,0.012392&t=h&z=17&layer=c&cbll=34.429505,-97.143864&panoid=3YoxuOY-PZfmPueGIy40yg&cbp=12,191.5,,0,0 (https://maps.google.com/maps?ll=34.429505,-97.143864&spn=0.000018,0.012392&t=h&z=17&layer=c&cbll=34.429505,-97.143864&panoid=3YoxuOY-PZfmPueGIy40yg&cbp=12,191.5,,0,0)
Title: Re: Cable guard rails
Post by: roadman on February 23, 2015, 07:56:11 PM
Quote from: Caboosey on February 23, 2015, 03:15:30 PM
I have been trying to get Caltrans (California DOT) to install one on Southbound Hwy 101 between Exit 191B and 191A in Pismo Beach, CA. The City of Pismo Beach want it, but Caltrans wont go for it. People can easily go off the road and hit cars on Price street / Hwy 1 head on. Someone already went off the road, Hwy 101 southbound, there once and killed two pedestrians on Price Street / Hwy 1 walking on sidewalk.

Location: https://www.google.com/maps/@35.1485899,-120.6492576,670m/data=!3m1!1e3 (https://www.google.com/maps/@35.1485899,-120.6492576,670m/data=!3m1!1e3)
Streetview: https://www.google.com/maps/@35.148824,-120.649219,3a,75y,124.94h,79.93t/data=!3m4!1e1!3m2!1ssSpSPn8vXVWAjpYDMA70qg!2e0 (https://www.google.com/maps/@35.148824,-120.649219,3a,75y,124.94h,79.93t/data=!3m4!1e1!3m2!1ssSpSPn8vXVWAjpYDMA70qg!2e0)

News article: http://www.sanluisobispo.com/2010/10/16/1330911_pismo-fatality-freeway-pedestrian.html?rh=1 (http://www.sanluisobispo.com/2010/10/16/1330911_pismo-fatality-freeway-pedestrian.html?rh=1)

Caltrans 2010 design standards for Cable guard rails: http://www.dot.ca.gov/hq/esc/oe/project_plans/highway_plans/stdplans_US-customary-units_10/viewable_pdf/b11-47.pdf (http://www.dot.ca.gov/hq/esc/oe/project_plans/highway_plans/stdplans_US-customary-units_10/viewable_pdf/b11-47.pdf)
Looking at the location, IMO you'd probably be better off lobbying for a standard guardrail instead a cable barrier due to the minimal lateral clearance between the 101 freeway and Prince Street.  This is because cable barriers are designed to deflect when hit, which could result in an errant vehicle still hitting pedestrians or vehicles on Prince Street.  Back to back standard W-Beam guardrails could be installed with the chain-link fence in between them.
Title: Re: Cable guard rails
Post by: adventurernumber1 on February 23, 2015, 09:22:01 PM
I've seen plenty of cable guard rails around here on interstates. Here's one on Interstate 75 in GA, even getting into Metro Atlanta: https://www.google.com/maps/@34.080103,-84.639649,3a,75y,76.67h,85.6t/data=!3m4!1e1!3m2!1sA8QRU6ugQ8jA7CwCAjvRZA!2e0

There's also a good bit on non-interstate freeways like sections of:
- US 19/GA 400: https://www.google.com/maps/@34.240723,-84.097548,3a,75y,197.57h,84.37t/data=!3m4!1e1!3m2!1sUr9rHP93xOyMNA_qM77a9w!2e0
- US 78/Stone Mountain Freeway: https://www.google.com/maps/@33.830556,-84.181543,3a,75y,94.05h,80.69t/data=!3m4!1e1!3m2!1sfwSNmrHm-rjBvR9w6wUcxw!2e0

I find them to be pretty cool, and a good alternative for generic guard rails.
Title: Re: Cable guard rails
Post by: slorydn1 on February 23, 2015, 10:38:38 PM
Quote from: slorydn1 on February 23, 2015, 01:07:00 PM
We have the cable barriers on both the US-70 freeway between Dover and the Freedom Memorial Bridge in New Bern, as well as on the new US-17 freeway alignment west of New Bern. The barrier on 70 has only been there for about 10 years or so, before that there was nothing but the wide median and luck.




Looking at other posts I should have included an example with mine:


https://www.google.com/maps/@35.099906,-77.055154,3a,75y,98.78h,90.12t/data=!3m4!1e1!3m2!1sFZ7S1TIWZcu66_bMy5kPog!2e0?hl=en


This is on US-17 North/US-70 East/NC-55 East at the approach to the Freedom Memorial Bridge (you can see where the cable ends and the normal guardrail begins up ahead). I like the DMS sign in the middle because the controls for it and the cameras sit on my desk at work.  :)
Title: Re: Cable guard rails
Post by: Caboosey on February 24, 2015, 03:15:11 AM
Quote from: roadman on February 23, 2015, 07:56:11 PM
Quote from: Caboosey on February 23, 2015, 03:15:30 PM
I have been trying to get Caltrans (California DOT) to install one on Southbound Hwy 101 between Exit 191B and 191A in Pismo Beach, CA. The City of Pismo Beach want it, but Caltrans wont go for it. People can easily go off the road and hit cars on Price street / Hwy 1 head on. Someone already went off the road, Hwy 101 southbound, there once and killed two pedestrians on Price Street / Hwy 1 walking on sidewalk.

Location: https://www.google.com/maps/@35.1485899,-120.6492576,670m/data=!3m1!1e3 (https://www.google.com/maps/@35.1485899,-120.6492576,670m/data=!3m1!1e3)
Streetview: https://www.google.com/maps/@35.148824,-120.649219,3a,75y,124.94h,79.93t/data=!3m4!1e1!3m2!1ssSpSPn8vXVWAjpYDMA70qg!2e0 (https://www.google.com/maps/@35.148824,-120.649219,3a,75y,124.94h,79.93t/data=!3m4!1e1!3m2!1ssSpSPn8vXVWAjpYDMA70qg!2e0)

News article: http://www.sanluisobispo.com/2010/10/16/1330911_pismo-fatality-freeway-pedestrian.html?rh=1 (http://www.sanluisobispo.com/2010/10/16/1330911_pismo-fatality-freeway-pedestrian.html?rh=1)

Caltrans 2010 design standards for Cable guard rails: http://www.dot.ca.gov/hq/esc/oe/project_plans/highway_plans/stdplans_US-customary-units_10/viewable_pdf/b11-47.pdf (http://www.dot.ca.gov/hq/esc/oe/project_plans/highway_plans/stdplans_US-customary-units_10/viewable_pdf/b11-47.pdf)
Looking at the location, IMO you'd probably be better off lobbying for a standard guardrail instead a cable barrier due to the minimal lateral clearance between the 101 freeway and Prince Street.  This is because cable barriers are designed to deflect when hit, which could result in an errant vehicle still hitting pedestrians or vehicles on Prince Street.  Back to back standard W-Beam guardrails could be installed with the chain-link fence in between them.

Caltrans kept complaining about the costs when i tried to push for regular guard rails, so I pushed for cable rails. I see about 4 cars per year going off of Hwy 101 and cross over into Price Street. I haven't seen any cars go off Price Street into Hwy 101 since there is a slight hill, lower speeds (speed limit is 35mph), and a fence.

Its about 15 feet from white line of Hwy 101 to the edge of road on Price Street.
Title: Re: Cable guard rails
Post by: hbelkins on February 24, 2015, 12:00:44 PM
New York uses this on NY 17:

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.millenniumhwy.net%2F2009_Milford_PA_Day_2%2FImages%2F17.jpg&hash=607c009928e665f3c9b948e82bd66fa67b06d401)
Title: Re: Cable guard rails
Post by: cbeach40 on February 24, 2015, 01:09:25 PM
MTO uses three cable guiderail as a roadside barrier on lower volume highways, in areas with a minimum of 3 m clearance from a hazard (due to the deflection of that barrier system). It is not used in median applications or adjacent to curb and gutter. Six cable guiderail with steel posts is technically permitted for median use, but cable systems in medians have fallen out of favour within the Ministry due to poor experience with them years back.

Cost wise, the installation and maintenance is actually cheaper than the "w-rail" barriers, with w-rail costing about 2.5 x as much to install, and 1.4 x as much to maintain (realistically, if a vehicle hits the barrier hard enough to knock out posts on a cable system it'll do some serious damage to the steel beam one too). The w-rail has a deflection of only 0.3-0.9 m, so it certainly is better at protecting from a hazard.
Title: Re: Cable guard rails
Post by: cpzilliacus on February 24, 2015, 01:34:07 PM
These used to be pretty common in Maryland years ago, but nearly all of them have been replaced by "W" beam barriers or Jersey wall-type concrete walls.
Title: Re: Cable guard rails
Post by: hm insulators on February 24, 2015, 02:34:11 PM
I think the stretch of Loop 101 in the western Phoenix metro area (by the football stadium) used to have cable guard rails down the center of the freeway but they'd been replaced by something more sturdy.

Anybody remember ordinary chain-link fence used to separate directions of travel? Growing up in southern California, the freeways all had ordinary chain-link fence down their centers. This was the 1960s and '70s.
Title: Re: Cable guard rails
Post by: kphoger on February 24, 2015, 06:39:26 PM
Quote from: kphoger on February 23, 2015, 02:27:41 PM
Quote from: Big John on February 23, 2015, 12:04:50 PM
Many states have put them in the median now as a lower-cost alternative to try to prevent a wayward vehicle from entering oncoming traffic.  Applies to wide depressed medians only. Placement is usually on one side of traffic rather than in the ditch.

This doesn't apply to wide, depressed medians only. Take a look at GSV for I-44 several miles south of Walters, Okla., for an extreme example.

Now that I'm at a desktop computer, I'll link to an example.
Cable barrier used between roadways of I-44 in Oklahoma.  Narrow, paved median space.
http://goo.gl/maps/mWzJg (http://goo.gl/maps/mWzJg)
Title: Re: Cable guard rails
Post by: Big John on February 24, 2015, 06:44:31 PM
^^ Whoa.  I would not trust that to prevent an errant vehicle from crashing into that and avoid entering the oncoming lanes.
Title: Re: Cable guard rails
Post by: adventurernumber1 on February 24, 2015, 06:51:39 PM
Quote from: Big John on February 24, 2015, 06:44:31 PM
^^ Whoa.  I would not trust that to prevent an errant vehicle from crashing into that and avoid entering the oncoming lanes.

I agree. A concrete barrier of appropriate height is much needed in that situation. I don't think I've ever seen a cable guard rail used in such a way.
Title: Re: Cable guard rails
Post by: Jardine on February 24, 2015, 07:03:01 PM
There might be more, but the I-29 overpass over the UPRR 1 mile north of Modale, IA has the cable barrier leading up to a W barrier leading up to the overpass railing.
Title: Re: Cable guard rails
Post by: SSOWorld on February 24, 2015, 07:24:21 PM
Lots of states have started using these "wait-a-minute" cables (as GR Van has dubbed them in his website) for years now.  I have seen them "in action" as there were may car grills caught up in them in northeast AR this weekend on I-55.
Title: Re: Cable guard rails
Post by: cl94 on February 24, 2015, 08:08:27 PM
Quote from: adventurernumber1 on February 24, 2015, 06:51:39 PM
Quote from: Big John on February 24, 2015, 06:44:31 PM
^^ Whoa.  I would not trust that to prevent an errant vehicle from crashing into that and avoid entering the oncoming lanes.

I agree. A concrete barrier of appropriate height is much needed in that situation. I don't think I've ever seen a cable guard rail used in such a way.

Yeah, that is not a good location for a cable barrier. Vehicle hitting it would go into the opposing lanes.
Title: Re: Cable guard rails
Post by: CANALLER on February 24, 2015, 08:52:24 PM
Road Man--

N.Y.S. still uses cable rail, although not as often as in years past.  In some areas, new runs are still being installed.  The white triangular posts you referred to were used as far back as the Depression, but all runs installed in the last 40-50 years use standard 3" I-posts.  They're called "Universal Posts" because they can be used with cable, W-beam, or box beam. 

The vast majority of rail installed is box beam, which we first designed in the '60's.  The basic design hasn't changed all that much since then, with the most noticeable difference being that the splice plates were originally outside of the joints.  There are a few runs with this feature still out there.

Although some runs of W-beam are still installed (particularly in W.N.Y.), the box beam is still the best choice, and looks a lot better than the W-beam used everywhere else in the country.  It can be used in any situation, and can seamlessly transition to bridge rail, culvert rail, across the face of an abutment or across any other obstruction.

The cable rails are still used in some areas too, particularly in the North Country where the snow really piles up.  The cables allow more plowed snow to go through them, which provides more room on narrow Adirondack roads.

The rails are also installed on the slope of a ditch, as you and others say.  This is to prevent errant smaller vehicles from actually diving under them and heading into oncoming traffic.

Several other comments also mentioned the amount of give in cable rails being much higher.  This is true under normal conditions, but it's "Deflection Distance" can also be reduced significantly by adjusting the spacing of the posts, like if the run is passing in front of a telephone pole.
Title: Re: Cable guard rails
Post by: roadfro on February 26, 2015, 01:57:41 AM
Nevada didn't use to use cable rails, but has started installing them in certain places in the last five or so years.

The wide median of US 395 in and south of Carson City are a couple of the earlier and more prominent locations.
Title: Re: Cable guard rails
Post by: GCrites on February 26, 2015, 09:09:43 PM
I just drove I-70 from Columbus to Springfield and I'd say almost half of the length of the cable barriers was compromised somehow.
Title: Re: Cable guard rails
Post by: D-Dey65 on July 04, 2016, 07:07:54 PM
Quote from: cl94 on February 23, 2015, 06:23:15 PM
New York still uses them, although they're mainly found on freeways. Typically placed in depressed medians or next to a gradual slope.
Really? Because most of the ones I've seen look like they're leftover from the 1930's or 1940's and many of them had the cables removed while the concrete poles remain neglected along the roads. I give you a road within Wildwood State Park (https://commons.wikimedia.org/wiki/File:Wildwood_State_Park;_Begin_SB_Suffolk_CR_54.jpg) as an example of this, but you can also find them on the westbound rest area on NY 27 in Bridgehampton.

Title: Re: Cable guard rails
Post by: cl94 on July 04, 2016, 07:13:56 PM
Quote from: D-Dey65 on July 04, 2016, 07:07:54 PM
Quote from: cl94 on February 23, 2015, 06:23:15 PM
New York still uses them, although they're mainly found on freeways. Typically placed in depressed medians or next to a gradual slope.
Really? Because most of the ones I've seen look like they're leftover from the 1930's or 1940's and many of them had the cables removed while the concrete poles remain neglected along the roads. I give you a road within Wildwood State Park (https://commons.wikimedia.org/wiki/File:Wildwood_State_Park;_Begin_SB_Suffolk_CR_54.jpg) as an example of this, but you can also find them on the westbound rest area on NY 27 in Bridgehampton.

Those are the old style. Newer ones are similar to this example on US 219 (https://www.google.com/maps/@42.6404156,-78.7639434,3a,75y,161.34h,79.39t/data=!3m6!1e1!3m4!1senk7elvh8GIpImGspmWcwg!2e0!7i13312!8i6656).
Title: Re: Cable guard rails
Post by: cpzilliacus on July 04, 2016, 07:15:19 PM
Maryland once used plenty of cable "guardrails," often mounted on timber posts, much more so in the pre-Interstate days. 

I do not believe they are used much, if at all, on the state-maintainted ("free" or toll) network now.  Steel "W" guardrail is very much preferred, usually just galvanized, sometimes Coreten or other brown shades (I-270 and Md. 200).

Virginia uses "W" guardrails as well as cable.  Not sure when or why they use one or the other.  An example from I-66 with cable on both sides of the westbound lanes is here (https://www.google.com/maps/@38.9808334,-78.2267693,3a,75y,296.6h,72.08t/data=!3m6!1e1!3m4!1slVKuqncAVAEHrKmDUybMrA!2e0!7i13312!8i6656), but not so far away on the eastbound side of the same freeway, here (https://www.google.com/maps/@38.9156246,-78.1008997,3a,75y,93.49h,69.31t/data=!3m6!1e1!3m4!1stzB-LwPHwg4gmYxyBiaUvQ!2e0!7i13312!8i6656) are "W" rails on both sides.
Title: Re: Cable guard rails
Post by: jp the roadgeek on July 04, 2016, 07:21:01 PM
CT has them in more rural areas, especially between Danbury and Waterbury on I-84

https://goo.gl/maps/k36CcfV5SQL2
Title: Re: Cable guard rails
Post by: D-Dey65 on July 04, 2016, 07:22:27 PM
Quote from: cl94 on July 04, 2016, 07:13:56 PM
Those are the old style. Newer ones are similar to this example on US 219 (https://www.google.com/maps/@42.6404156,-78.7639434,3a,75y,161.34h,79.39t/data=!3m6!1e1!3m4!1senk7elvh8GIpImGspmWcwg!2e0!7i13312!8i6656).
Yeah, I was wondering about those old style ones. When did they really start to do away with them? I used to see plenty of them still around in the 1960's.



Title: Re: Cable guard rails
Post by: SignGeek101 on July 04, 2016, 09:13:57 PM
Like this? https://goo.gl/maps/vVMB2sukLju

Their common throughout Ontario, mostly in rural areas. I'm not sure whether the MTO is still using them in new installs or not.

Title: Re: Cable guard rails
Post by: 7/8 on July 04, 2016, 09:50:20 PM
I had a co-op at the MTO last fall (2015) doing roadside safety OPSDs (standard drawings) and I believe their policy is cable guide rail is okay on lower traffic, rural roads due to being more economical. Of course, there needs to be sufficient room on the other side to allow for the high deflection of cable guide rail.
Title: Re: Cable guard rails
Post by: TheHighwayMan3561 on July 04, 2016, 10:05:52 PM
Minnesota has become a very heavy user of these on rural interstates in the last few years.
Title: Re: Cable guard rails
Post by: PurdueBill on July 04, 2016, 10:21:50 PM
Peabody, Mass has an example (https://www.google.com/maps/@42.5494363,-71.0035777,3a,66.8y,-178.39h,68.55t/data=!3m4!1e1!3m2!1s6BBOeZ0eDWerPjf9Jn6knQ!2e0) of ancient Massachusetts cable guardrail that used to be much more common--triangular concrete posts with two lines of cable.  As can be seen, this specimen is in really terrible shape with rebar exposed and all there is to a couple posts even.  Peabody probably will not replace it until it is hit and requires replacement at the expense of someone's insurance or something!

A more modern version had metal I-shaped posts like modern guardrail with three cables threaded through circular/elliptical holders at each post.  Examples still exist here and there but are harder to find every day.

The modern cable barrier for medians that has been installed in many states lately is really a different kind of animal than the ancient types.  The modern one is aimed at avoiding crossover accidents, while the really old stuff was for all the purposes of a guardrail (which it wasn't necessarily great for).  The examples of median cable barrier that is very recent are a different kind of thing than the old kind which has been replaced by modern W-shaped rail.
Title: Re: Cable guard rails
Post by: UCFKnights on July 05, 2016, 12:15:51 AM
I believe Florida has only started to use them in the past few years, since having a large grassy median was determined to be no longer enough to seperate directions of traffic. At the very least, they have become much more prevalent. With more rules just being past that most of our retention ponds on all roads need guardrails now too, I imagine we'll see them there as well in areas that would previously have gotten nothing.