A researcher at the Texas A&M Transportation Institute (TTI) has come up with an automated way of determining how well ditches found along Texas roads and highways are handling rainwater as it flows off the pavement. Charles Gurganus, associate research engineer in TTI’s Pavements and Materials Division, is studying an automated method of providing the Texas Department of Transportation (TxDOT) with right-of-way-line to right-of-way-line roadway surface geometric information, based on TxDOT’s extensive collection of data documenting the performance of the state’s roadways. If successful, the TTI project could help Texas significantly improve how wisely it spends taxpayer funds on its roads and highways.
Using LiDAR, Gurganus can collect extensive roadway geometric data, including roadway cross slopes, super elevations, front slope steepness, and drainage areas of a roadway. The technology can also determine the depth of a roadside ditch and its offset related to the nearby pavement structure. All data can be collected at highway speeds.
The technology is a single, boom-mounted laser device mounted 10 feet in the air. It also uses GPS technology, an inertial measurement unit, and a video camera.
Gurganus hopes to link road distress problems to the collected data. “We know this roadway is having performance problems from a distress standpoint,” he said. “How does that relate to ditch depth and offset? If a roadway is performing poorly, such as alligator cracking or rutting, we can now show that it has a shallow ditch close to the pavement’s edge. If repairs are going to be made, we can deepen the ditch and move it away from the pavement. It’s a more holistic repair approach.”
Data has been collected from roadways in TxDOT’s Austin, Brownwood, Bryan, Atlanta, Tyler, and Corpus Christi districts. The challenge is taking that data and deriving useful information from it. In 12 miles of roadway, the system can generate 25 million points. As Gurganus noted, it’s “how to go from being data rich to being information rich? How do we supply the client with information-rich data that meets their needs?
“If we can begin to integrate this information into project development, it will give TxDOT more information so that their project scopes can be more refined,” Gurganus said. “This should help them stretch their funds farther and do more lane miles of work every year. Maintenance supervisors will be able to focus on problem spots with measurable data. Time, effort, materials, and money will impact roads that really need it.”
Information provided by Texas A&M Transportation Institute (https://tti.tamu.edu).