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Thread: "Cat's eyes"

  1. #1

    Default "Cat's eyes"

    I don't know what else you call them, they are the two bright objects that are set on the road in many roads throughout the world but for some reason I rarely see them here. I assume it is because of the cold temperatures here, but they are just great visual tools. Your expertise or comments are appreciated....
    We are all the same, just different...

  2. #2

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    do you mean as opposed to having painted lines?

  3. #3
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    i think the snow and ice would cover them and render them pretty useless in teh winter. plus the snow plows might shear them off.

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    Nobel that is precisely the reason why they aren't seen much here, in some of the northern states they do grind a notch into the asphalt and place them in the notch so the blades won't scrape them off.

  5. #5

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    Quote Originally Posted by nobleea View Post
    i think the snow and ice would cover them and render them pretty useless in teh winter. plus the snow plows might shear them off.
    In the United States, they are also known as "Bott's Dots" after the inventor. And yes, that's pretty much why you don't find them here, or in places in the US that see snow.

    http://en.wikipedia.org/wiki/Botts'_dots

  6. #6

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    searching wikipedia also reveals that they are also called cat's eyes!! I never heard either of these terms before!!
    http://en.wikipedia.org/wiki/Cat%27s_eye_(road)

    http://en.wikipedia.org/wiki/Raised_pavement_marker

  7. #7
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    Snow and Ice melt fill em up and freezes resulting in blasting them outa the road creating the start of a pothole

  8. #8

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    Thanks for the replies and links. In Medwards' second link there is a snowplowable marker but yes it would be awkward here but they are great devices, the middle of the road just lights up ahead of you.
    We are all the same, just different...

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    So are these in place where the lines in the road currently are in our roads? I know I'm getting annoyed that half the lines in our city streets are practically non-existent.

  10. #10

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    Quote Originally Posted by etownboarder View Post
    So are these in place where the lines in the road currently are in our roads? I know I'm getting annoyed that half the lines in our city streets are practically non-existent.
    They are in place together with the lines. When car headlights shine on them they light up, so for example you can clearly see the road is winding to the left or right ahead. I agree that our roadway lines need painted more often, especially at cross walks where often they are non-existent.

    See here: http://www.roadtransport.com/blogs/b...blog/cats1.jpg
    Last edited by [email protected]; 11-02-2009 at 11:51 AM. Reason: added picture
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  11. #11
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    just to relight an old fuse:
    You cannot see the lines because of all the sand they use.....

  12. #12
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    No, I can't see the lines cause they just don't exist... unless you mean the sand scrapes off the paint, then maybe. I know the lines do not exist and it's not just because the roads are filthy and covered in sand cause I actually got out to look one day.

  13. #13

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    ^^ oh no you didn't. You didn't go there did you? Oh you did... baaaaaaaam

  14. #14
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    On a related note
    ---
    Traffic Stripes Get A Brighter Future
    Byte - Ben Mack March 12 2009

    A bunch of professors armed with a gadget called a "retroreflect-o-meter" say painted roadway markings like the stripes dividing lanes are much more effective if they're applied in the same direction the traffic flows.

    That may seem like a classic "so what" kind of discovery, but the researchers behind the North Carolina State University study say the findings could help state and federal highway authorities comply with forthcoming federal safety regulations and save millions of dollars on paint.
    http://www.trafficmarkings.com/pdf/R...face-Guide.pdf

    Some 60 percent of the nation's roads are marked with paint, and study co-author Dr. Joseph Hummer says the "retroreflectivity values" of such markings are higher in the direction of the striping. In other words, the paint reflects more light if the paint truck is going the same direction as traffic. The difference is equivalent to about a year of wear and tear, meaning the markings will look "one year newer" if you're going the same direction the paint truck was.

    Hummer says the discovery could help federal and state transportation departments more accurately predict the frequency with which roads must be painted - an endeavor that can cost $2,000 to $3,000 per mile - and better develop a standard for measuring the brightness of painted traffic markings.

    More importantly, Hummer told us, it could increase safety.

    Reflective02 A couple grand per mile may seem like a lot of money for paint, but it's still cheaper than using thermoplastics and other materials.

    Paint takes a beating under all those tires, though. Roads in the northeast take the most abuse during the winter. Snow tires, road salt and snowplow blades play hell on the paint, which is why Massachusetts has to repaint its roads every two to three years and Maine slaps a new coat on 8,000 miles of road every year, according to The Boston Globe.

    When roadways are restriped, glass beads are scattered onto the paint (see the photo) to make the markings reflective. The researchers found those beads tend to bounce and roll because the paint truck is moving, reducing reflectivity. "The beads skid and build up paint on one side," Hummer said. "Therefore, they are less reflective in that direction."

    The Federal Highway Administration is drafting new standards dictating how and when road markings should be applied. Hummer says his findings raise the possibility a painted line could pass the new brightness standard if tested in one direction but fail if tested in the other.

    Hummer realizes most paint trucks travel in the same direction of traffic but says his study is more concerned with the lines dividing opposing lanes of traffic - like the yellow dividing lines in the main photo - because those tend to be painted simultaneously. That makes them brighter in one direction than the other. "The center line is the most important line on the road, and it's brightness will have an effect on the way we drive," he said.

    Don Rowell, a regional sales manager at Advanced Traffic Markings, said he couldn't comment on Hummer's findings until he'd read the study but says one must also consider the cost-effectiveness of shutting down both lanes of traffic to restripe a road. His firm carries a wide variety of road marking equipment but doesn't offer paint. Instead it sells plastic tape. It costs 40 cents more per foot than paint, but it already has the glass beads embedded in it, rendering the reflectivity issue moot.

    The study, "The Impact of Directionality on Paint Pavement Marking Retroreflectivity," appears in the journal Public Works Management and Policy.

  15. #15

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    BBC News - Glow in the dark road unveiled in the Netherlands
    http://www.bbc.com/news/technology-27021291
    Excerpt:
    "Glow in the dark road markings have been unveiled on a 500m stretch of highway in the Netherlands.

    The paint contains a "photo-luminising" powder that charges up in the daytime and slowly releases a green glow at night, doing away with the need for streetlights."...

  16. #16

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    Still, when covered by sand and gravel, the markers are rendered useless.

    The solution, clearly, is photoluminescent gravel, or magic sand.

  17. #17

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    Quote Originally Posted by Legacy View Post
    Still, when covered by sand and gravel, the markers are rendered useless.

    The solution, clearly, is photoluminescent gravel, or magic sand.
    Brilliant! And it's portable. You get to work on that ok. I hear there's glowing sand for that taking just outside the Fukushima plant in Japan that doubles as snow melt too.

  18. #18
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    I am impressed when they built the Coquihalla near the pass they put up lights, in the snow this can make a HUGE difference in being able to see the road, ice and snow and not. Not sure if photoluminescent paint would make much of a difference, perhaps it would as snow and ice both allow some light to pass through.

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