Sealing cracks in a road may sound simple enough: Send a crew to close the traffic lane, spray on a sealant, let set, reopen the lane and move on to the next crack. However, it requires an investment in manpower and creates a safety risk for the workers tasked with doing the job. Yet the benefit of cost avoidance makes it a task that can’t be ignored.
“Crack sealing can be a tremendous money saver, if it’s done right and done in a timely manner to prolong pavement life,” said David Jared, acting chief of research and development for the Georgia Department of Transportation (GDOT).
With GDOT funding, researchers are proving that an automated system is feasible. The Georgia Tech Research Institute (GTRI) created a prototype for an automated pavement crack detection and sealing system that located and filled cracks smaller than one-eighth inch wide while moving at about 3 mph.
“We demonstrated the concept, and I think that GDOT looks to the future and looks at trying to be more efficient,” said Wayne Daley, principal research engineer with the GTRI.
One key function was that the system needed to be able to seal cracks while in motion, an aspect that was solved with technology similar to inkjet printing. To locate cracks, LEDs illuminate the road while a stereo camera takes pictures, which are analyzed by algorithms. Within 100 milliseconds of taking the images, a computer generates a map detailing the location and shape of the cracks, according to the GTRI.
The prototype seals one square foot of a cracked area at a time. Production versions would be 12 feet wide to match the size of street lanes.
Jared said one of the greatest benefits is better safety for crews. With this machine, they can stay in the truck and operate the system (which is on a trailer towed behind the vehicle), instead of physically being in the roadway.
Now that the idea has been proven, GDOT hopes that industry will step in and take over further development. “It’s a viable technology, and we’re looking for assistance to take it to the next step,” Jared said.
Photo courtesy of the Georgia Tech Research Institute. Read about more dirty jobs in government
