by Mary C. McCarthy
The Connecticut Transportation Institute in conjunction with the Connecticut Department of Transportation, the Federal Highway Administration and the Connecticut Department of Energy and Environmental Protection has developed a specification to use post consumer waste asphalt shingles in asphalt pavement. The Connecticut Department of Transportation is piloting this new specification on a construction project on Route 220 in Enfield, CT this coming summer.
Post consumer waste asphalt shingles are typically old shingles that have been removed from residential structures. The uses for this waste product are very limited, but the high asphalt binder content of the shingles makes using them in asphalt pavements an attractive option particularly as the price of oil continues to increase.
The waste shingles must be processed to remove all of the other waste materials such as metal and wood. The shingles are then ground up so they can be easily mixed into the asphalt pavement. The asphalt binder used in roofing shingles is considerably harder than what is used for pavements and therefore the pavement must be designed to account for this harder asphalt binder.