January 21st, 2011

RETROREFLECTIONS ON PAVEMENT MARKINGS

Preserve Infrastructure, by Catherine Higgins.

UDOT is improving pavement marking visibility at night during storms.

Glass beads and grooving: This image from a UDOT report on improving pavement marking retroreflectivity shows glass beads and reflective beads added to paint. Grooving pavement before applying markings is a way to avoid plow blade wear and tear.

Road users are sometime frustrated when pavement markings are less visible at night during storms — and for good reason. “We realize this issue is a safety concern,” says Ken Berg, UDOT Maintenance Planning Engineer. “Pavement marking visibility is our number one safety priority here in Maintenance all the time, but especially in wet weather and at night.”

Pavement marking visibility can be reduced because of water on the road and wear caused by snow plow blades.

Water interferes with the reflectivity of pavement markings. “Light is refracted in all directions through the water, rather than retro reflected back to the driver,” according to Berg. One way to combat this reflectivity issue is to add profile, or thickness, so markings are visible above the water.

Adding profile can be accomplished by using thicker products or adding glass beads to the paint. However, high profile markings can get scraped off by snow plows. ”Thicker markings won’t usually last through the winter,” says Berg. “So, the increased cost of thicker markings isn’t usually justified.”

UDOT is studying ways to counter water and plow blades.

Dan Betts, Region 2 Pavement Marking Coordinator and Berg are developing application methods that can be used by state forces without expensive materials or special equipment. Betts has developed and refined the process of cutting a groove in the pavement so paint is recessed below the surface. Recessed markings are less likely to be worn down by snow plow blades.

In addition to grooving, adding retroreflective glass and ceramic beads to paint improves visibility during wet and dry conditions and at night. Tests done at night confirm the effectiveness of the beads.

For more information, see a report on the process conducted on I-84 in Weber Canyon.

Back Top

Responses to “RETROREFLECTIONS ON PAVEMENT MARKINGS”

  1. Grooving may protect the new reflective markings from snowplow blades, but won’t the grooving also compound the problem of water refraction? Presumably, the grooving process results in markings that lay on the same plane, or even below that, of the tradition road surface markings. As such, won’t the new markings be covered with an equal or greater (due to pooling of water in the groove) amount of water during a weather event. Thank you for allowing us to express a simple curiosity.

    Richard Wilkinson at January 21, 2011 5:40 pm
  2. This would be awesome to see here in Utah. Our freeway line markings could really use a boost. Some stretches of road are hard to see even in clear conditions at night. Another idea should be to first paint wider black lines on the roadway prior to painting the white lines on concrete stretches of freeway (Such as here: http://www.aaroads.com/west/colorado085/us-085_nb_santa_fe_drive_09.jpg).

  3. Another issue is premature pavement deterioration due to pavement markings. This is probably addressed in the I-84 report, that I haven’t had time to read.

    One advantage of concrete pavement, is that people can often discern edge-of-travel-lane (EOTL) by the joints in the concrete. Our Region One Materials Engineer, Scott Nussbaum, has pointed this out to me several times. Grind-in markings on concrete pavement do not have the same deteriorating effects as they do on asphalt pavement, although they can’t be placed directly on the joint, and can be thus slightly off the EOTL. The markings on concrete pavement seem sufficiently visible to me, especially when white markings are placed on a black paint background.

    Two major disadvantages of concrete pavement are the higher initial cost, and less flexibility in shifting lanes at a later time. Concrete pavement does not fare as well as asphalt pavement when the wheel-paths of vehicles are shifted on to the joints. But I digress…

  4. Grooves may be a good idea for the reflective paint, but WHY would you put grooves throughout every lane???

    UDOT, have you driven your personal vehicle on the new pavement you’re putting down? I’m not talking about your trucks. Try driving an economical car on your new surface. The grooves are horrible for smaller tires. My wife’s Prius, with its small tires and small width, is absolutely brutal on your new surface.

    We’ve had to endure years of construction, and were pretty excited to see our stretch (Springville) nearly complete – only to be extremely disappointed in your choice to put grooves down everywhere. It catches tires, and has got to be a MAJOR safety and liability issue.

    Not pleased at all.

  5. Scott,

    You may be noticing something different than pavement marking grooves, such as damaged pavement. The grooves for pavement markings are about the thickness of a quarter. UDOT has tested the grooves for how tires react when crossing paint marking grooves. A typical car or motorcycle driver may feel the groves during a lane change, but crossing the grooves should not cause any bumping or jarring motion at all, even in a small car.

    If you give me the location where your wife is experiencing difficulty, I would be glad to research what is going on at that location and respond with an answer.

    Also, I have contacted the I-15 CORE Team to ask about about how the finished pavement in the Springville area — I will update this answer when I get that information.

    Thanks for your comment.

    Catherine Higgins at April 18, 2011 4:07 pm
  6. I am glad to have found this blog tonight, especially ironically enough having traveled through Springville and all the Utah County construction today. I’m in that area frequently although I live in Evanston (WY). I think even with all the new technology paint and tape and grooves, the markings still can and do disappear with a good amount of water on the road. Case in point…..about 2 weeks ago coming home from Salt Lake, heading up Parley’s Canyon. Wet snow causing a good bit of water on the roadway. Nobody could see the markings. And yet the same though keeps coming to my mind. Why doesn’t Utah just use recessed reflectors like some other states?? (And yes I will be asking the same of WyDot as well because we don’t have ‘em here either) I grew up in Louisiana and all our markers are above the pavement. Of course that wouldn’t work here in the west….I understand that. The plows will rip them right off. But go down to Arizona and in snow-proned areas there are still reflectors. Kingman area and all of I-40 is a good example. U.S. 93 from Las Vegas to Kingman as well. The reflectors are recessed in a groove so that they still work….even when there’s water on the road. And since they are recessed, the plows don’t break them off. I moved to Utah in 1986 and I seem to recall Utah had started doing a lot of them. I-215 for example. Almost all the concrete sections of 215 had them. I was on U.S. 40 today….the nice concrete section from Heber to Silver Creek Junction. That road used to have them too. Yet now, and as has been the case for several years now, they’ve been ripped out and filled in with concrete or asphalt or whatever. Why?? Wouldn’t these lead to safer roads? Wasn’t Utah on the right track? Who changed their mind and decided to fill in all the recessed reflectors? A couple of years ago I traveled to New York and most of their freeways…..Pennsylvania…Ohio…. they all have reflectors and they are just recessed. Believe me it worked great. It was a RAINY trip down I-17 through Pennsylvania and all you COULD see were the reflectors….you couldn’t see the stripes of paint or tape (whatever they use over there). Just curious why the state decided NO to recessed reflectors.

    Thanks
    Michael – Evanston, WY

  7. Dear Mike,

    Thanks for posting on the UDOT Blog. I spoke to Shana Lindsey, a Maintenance Methods Engineer at UDOT. According to Lindsey, you are right that UDOT did use reflective lane marking but discontinued the practice due to several reasons.

    The reflective markers were made of metal and the edges tended to pop up causing havoc and even breaking very expensive snow plow blades. Plus, a loose marker could cause safety hazard to motorists. Utah’s freeze thaw cycle, which makes pavement heave, also caused the markers to come loose.

    A year after installation, the reflectivity of the markers deteriorated and lost all effectiveness. Removing and reinstalling those worn out markers was a high cost compared to the benefit to motorists and tax payers. Shutting down lanes to do time consuming work impedes travel and replacing a reflector that wears out quickly does not make good economic sense for tax payers.

    Overall, grooved-in paint seems to be the best solution to the difficult problem of providing reflectivity on travel lanes. UDOT is a very forward-looking agency and engineers are actively seeking new technologies that may provide better reflectivity at night and during storms.

    You also mentioned driving through Springville and the I-15 CORE construction. I spoke to Leah Jaramillo, I-CORE Public Information Manager, who says that lanes through the construction zone are repainted as often as possible. It has been challenging for the contractor to re-paint lanes during the wet spring weather, but re-painting is important and the contractor gives priority to the task.

    For information about the construction on I-15 CORE, be sure to check out the website at http://www.i15CORE.utah.gov

    Happy travels through Utah, Mike!

    Catherine Higgins at April 26, 2011 4:17 pm
  8. This would be awesome to see here in Utah. Our freeway line markings could really use a boost. Some stretches of road are hard to see even in clear conditions at night. Another idea should be to first paint wider black lines on the roadway prior to painting the white lines on concrete stretches of freeway

  9. Another issue is premature pavement deterioration due to pavement markings. This is probably addressed in the I-84 report, that I haven’t had time to read.

  10. This would really help where I live. At night on the hiways after it rains you can’t see any markings anywhere

  11. According to my experience Grooves may be a good idea for the reflective paint. Thanks a lot for your time and energy to have had these things together on this blog. I very much appreciated your helpful knowledge through your articles on certain things.

  12. I think the groove idea is a great one, especially when combined with the glass beading for improved reflectivity.

  13. Here in Ohio they started grooving under the pavement markings and it has increased the life of the pavement making substanually. The grooving it’s self is very shallow and does not seem to increase the problems that occure with reflected glare during rainy weather. The only thing that seems to help with that is the reflective units inbedded in the road. They last for a substantual amount of time here but their edges are sealed into the road surface and the reflective material is a high grade heavy duty reflective tape (they originally had a hard plastic that got crushed by the plows.

  14. Christine, that’s very interesting. Can you send me some product information? I’d like to find out more.

    Catherine Higgins at January 5, 2012 3:24 pm
  1. Tweets that mention REFLECTIONS ON PAVEMENT MARKINGS ­ UDOT Transportation Blog -- Topsy.com (,January 24, 2011)

    [...] This post was mentioned on Twitter by Utah DOT, Sherry Shadday. Sherry Shadday said: So incredibly helpful! RT @UtahDOT developing ways of improving pavement marking visibility at night & during storms http://bit.ly/fgyiaZ [...]

Leave a Reply

Back Top