(logo whooshes)
- [Narrator] Maintaining and improving roadways
often requires changing the pavement markings,
a method commonly known as restriping.
Because markings are designed to last
despite weather and road use,
getting rid of the old ones can be challenging.
Old markings, called ghost markings,
should be completely removed
to accomplish effective restriping.
Researchers at the University of North Texas
evaluated the use of lasers
as one possible new alternative
for removing the old markings.
- We had two things that really kind
of led us to this research.
I'd say the first thing was ghost marking.
So, this is a case
in which you have pavement markings,
that we go out there,
and that we have to remove
for one reason or another.
And so, we'll go out there,
we'll use some type of flailing or water blasting
to remove the existing marking,
and what it does is
it typically leaves a scar on the surface,
and then sometimes it might leave a little bit
of that residual marking.
The second thing, though, is we kind of wanted
to look at the state of the practice.
It's been a while since there's really
been a detailed analysis on different methods.
And so, one of the things that had been proposed
to the state was laser removal,
and so that was one of the things we also
had a chance to kinda look at, laser removal in comparison
to water blasting, flailing,
any of a number of different techniques
that are available to us.
- Primary research objectives
of the project were mainly two.
So, the first one is to seek, basically,
understanding on what is in use
in the state of Texas and other states,
what are the pros and cons?
The second part of the project
was to develop a laser system prototype
to test first in a lab and then in the field.
We find out that the equipment works well.
So, basically, we safely remove the stripes
from concrete (indistinct).
However, if you compare this technique
with current techniques,
basically, the speed of removal was limited.
We know that there is another technology
that can be used in place of current technology
that, if perfected, can reach,
potentially, the same removal speed
of the current technologies.
Of course, further research would be needed
for improving the system and to make it viable.
- We were really hoping that laser
would be a great method to go and remove
and not cause any scarring to the surface
and completely remove the marking.
It didn't work out that way,
and that's okay.
Sometimes that's what it is in terms of research.
You have an idea, you go out and you test it,
and you find out,
"Well, it's not the way we wanna go,"
but I think it points us in the direction
to the next question we need to ask.
How do we use the existing tools
that are available to us
to accommodate the concerns
over this ghost marking?
And then can we update the documentation
to give kind of a refresh to our staff?
- [Narrator] For more information
and to find the publications for this project,
please visit the TxDOT Research Library
at the link shown below.