State tests 'perpetual pavement' for highways

By KRISTA CHAMBERS
Capital News Service
LANSING — A pavement project taking place on Telegraph Road in Wayne County could end up extending the life of roads across the state.
Perpetual pavement, a type of pavement used in European countries, is being tested by the Michigan Department of Transportation to see if it would benefit other roads in the state.
According to MDOT Director Gregory Rosine, southeastern Michigan has poor conditions for roadbeds, making it a prime target for progressive asphalt techniques.
“Southeast Michigan has the worst conditions in the state for roads because of its clay beds underneath the pavement,” Rosine said. “Those clay beds are slippery, and they slide around, causing lots of road damage.”
Perpetual pavement, however, could be a solution, although an expensive one.
“Basically, it’s based on European models,” said Stephanie Litaker, a communications representative for MDOT. “The base underneath the pavement is built thicker and stronger, so the road deteriorates from the top to bottom, instead of the bottom to top.”
The cost of perpetual pavement runs roughly 10 percent higher than average road paving costs.
The perpetual pavement is built with a thicker base than usual, allowing the top layer of pavement to be taken off and rebuilt more easily than redoing the entire road.
“The big difference, other than being one and-a-half inches thicker than normal pavement, is we use a premium-grade asphalt liquid and a premium-grade asphalt stone in that liquid,” Litaker said. “The deterioration rate is slower than normal this way.”
Typical pavement thickness is two feet, while perpetual pavement thickness measures 25.5 inches.
“Angelo Iafrate Contractors from Detroit came to us at MDOT and said they wanted to try it,” Litaker said. “A project to redo a stretch on Telegraph Road was already in the design phase, so we decided to test the perpetual pavement on that stretch.”
Litaker said MDOT was worried about testing the more expensive pavement, running the risk of wasting taxpayers’ money.
“Typically, there’s no warranty on a stretch of pavement,” Litaker said. “However, we didn’t want to put taxpayers at risk, so the contractors gave us a five-year warranty on the test stretch of road.”
The pavement project is being tested on a one-mile stretch between Grand River Boulevard and Six Mile Road on Telegraph Road, also known as U.S. 24.
The project, if successful, could more than double the life of roads in parts of Michigan.
“The typical life of normal pavement is 20 years,” Litaker said. “With perpetual pavement, the estimated life of the road would be 50 years.”
As for measuring the benefits of perpetual pavement, it could be a while. “It could take a long time before we know if the increase in cost will be worth it,” Litaker said. “We’re watching data from other parts of the world who are using this method to understand the benefits.”
© 2002, Capital News Service, Michigan State University School of Journalism