WSP is the lead designer for the installation of smart pavement technology along a half-mile section of U.S. 285 north of Fairplay, Colorado. Developed by Kansas City-based Integrated Roadways, the “smart pavement” technology uses precast concrete pavement slabs that are embedded with intelligent transportation system elements—specifically, upgradable sensors capable of identifying where cars are located, the direction they are moving, and how fast they are going.
Smart pavement technology works with all vehicles using the road.
“The sensors in the pavement create a ‘footprint’ of the vehicle on the roadway,” said Tim Harris, WSP client relations manager. “It detects all vehicles, so there is no electronic communication and no special vehicle technology is required.”
The Smart 285 team also includes Kiewit Infrastructure Company as the lead construction firm, and Wichita Concrete Pipe as the concrete panel fabricator.
The design phase of the project started recently, and pending results of a smaller proof-of-concept installation along a Denver roadway, construction on U.S. 285 could begin in spring 2019, with completion of the project targeted for later in the fall of that year. Integrated Roadways will operate and maintain the system for a one-year evaluation period after its completion.
This heavily traveled stretch of U.S. 285, which connects to recreational areas popular in the summer months, was selected for the pilot program by the Colorado Department of Transportation (CDOT) due to its high rate of vehicle accidents involving motorists departing the roadway.
The mountainous and winding highway has a reverse curve at the end of a long straightaway, where run-off-the-road accidents are frequent, resulting in an accident rate nearly three times the average rate in that region. Accidents are usually single-vehicle incidents involving drivers unfamiliar with the area who lose control of their vehicles and leave the roadway—often in inclement weather conditions.
“This is an exciting opportunity to introduce a game-changing highway technology that will improve the safety of motorists in Colorado,” Harris said. “CDOT is very interested in using new technologies and we are thrilled to have the opportunity to collaborate with them on this implementation.”
Each pavement panel includes four sensors. Harris estimates that about 200 panels will be installed for this project.
Those sensors allow the pavement to alert authorities if a vehicle has exited the driving lane along those curves at a speed and trajectory that indicate it has left the road. When this happens, the CDOT Traffic Operations Center will be alerted and will notify emergency responders.
The project includes the design and construction of a small “fiberhut” micro data center adjacent to the reconstructed highway, which will collect segment-length data from a series of vaults connected to the sensors that can immediately alert authorities to a problem. That data can also be used to recreate an accident scene and help CDOT evaluate mitigating factors that could lead to effective road safety improvements for this site and comparable locations.
The project will require a lane closure during construction to remove the existing pavement, regrade the roadway, and place the precast concrete panels. The Smart 285 team will minimize the impact on traffic with open and continuous communication with local agencies and motorists, and limiting closure to one-way traffic during working hours, and one-lane travel during non-working hours.
“Our biggest anticipated challenge will be weather conditions during construction, as the site is at an elevation of almost 10,000 feet,” Harris said.
Smart pavement can detect ice and snow buildup to alert when maintenance would be required, as well as prevent unnecessary and costly attention if conditions are fine.
The pavement is also upgradable. Future versions will incorporate wireless services to communicate real-time vehicle position information directly to connected/automated vehicles.
The roadway can generate revenue from data and connectivity services. Smart pavement also has the potential of using private investments to improve public infrastructure without implementing tolls.
If the Smart 285 program proves successful, it could pave the way for future integration on other roadways.
“We could likely see more installations at locations showing high run-off-the-road incidents,” Harris said. “It could also expand to include more direct communication with vehicles. Opportunities could even exist on commercial properties for traffic or parking management purposes.”
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