Infrared pothole repair system demonstrated at Briarcrest

LACONIA — Mark Twin once quipped "This is the only place in the world where the pavements consist exclusively of holes with asphalt around them. And they are the most economical in the world," he continued, "because holes never get out of repair."

Yesterday a number of public officials and curious residents gathered at Briarcrest Estates got a close look at infrared technology, a technique for repairing potholes, cracking, cuts, manholes joints, drains and other defects in asphalt surfaces in less time and at less cost than conventional methods.

Don Vachon, the operations manager of the Lakemont Cooperative, which purchased the Briarcrest manufactured housing park earlier this year, invited Roger Filion, president of Kasi Infrared Corporation of Newport, N.H., to demonstrate the technology on a steep slope riven with cracks. Vachon explained that after 30 years the roads in the park are showing signs of wear and, bound by a tight budget, he sought an alternative to paving.

Kasi Infrared has been manufacturing the equipment and applying the technology for the past 15 years. The first step in the process is to clean the area being repair of standing water, loose asphalt and dirt. Then the 48-square foot infrared chamber, attached to rear of the truck, is positioned over the area to be repaired so that its edges are at least six inches from the damage. It takes between five and eight minutes to heat the asphalt to 325 degrees Fahrenheit to a depth of two inches.

The infrared chamber is lifted and the damaged area is scarified with a rake, leaving a shallow trough at the edges. A six inch perimeter of heated asphalt is left undisturbed to ensure that when the repair is rolled the hot asphalt in the restored area is fused to the heated roadway to eliminate any seam. Asphalt, carried in the hot box on the truck, is raked over the site, which smoothed and leveled with a lute. Finally the restored area is rolled with at least 2,000 pounds per square inch of pressure.

Filion said that repairs can be made with a crew of two and one truck, which carries the infrared chamber, hot asphalt, roller and tools. He stressed that the infrared technology can be applied throughout the year and unlike cold patching "once you've made a repair, it's done. You're not going back."

Paul Moynihan, diretcor of Laconia Public Works, said that "we think it has its applications. Not in all places, but where there are a lot of potholes, like Court Street."

John Neal, general foreman of the Department of Public Works, who has worked with the technology, said that early this spring on Court Street alone some 50 tons of material was used to patch potholes, many of which washed out with the next storm. He said that each pothole had to dug out to the gravel, then filled. A crew of five or six, including flaggers, was required. He suspected infrared technology, with a cost of $4.50 a square foot or a daily rate, might offer a more effective and less expensive alternative.

The difference between infrared technology and conventional methods, Filion explained, "is that they're going to be going back, and back and back. Once this is done, it's done. It's going to save everybody money in a big way."

Fillion and his crew were in Briarcrest at the invitation of Vachon, who is one of a number of residents now charged with the running of their community, where all the roadways are owned by the cooperative.