PAVEMENT RECYCLING

By JOHN McCREE
Illinois Department of Transportation

The 1987 roadway improvement season is rapidly drawing to a conclusion. It is time to take stock of your highway or street system and begin to plan for your next year's improvement program. With today's climate of increasing costs and decreasing revenues, public officials are consistently being asked to make their highway dollars stretch farther than in the past. An increasingly attractive approach to roadway rehabilitation is to investigate various methods of pavement recycling. Recycling offers an opportunity to economize on energy and material costs by re-using some or all of the existing roadway components. There are a number of recycling alternatives that will aid in extending the service life of a road or street.

Recycling of Bituminous Surfaces

Bituminous surface recycling can be accomplished by cold milling and hot mix recycling or by using a heating, scarifying, rejuvenating and relaying process.

Full Depth Recycling of Flexible Pavements

Existing Flexible pavements may be pulverized, mixed with a stabilizing agent and recompacted as a new full depth flexible pavement. Equipment is currently on the market that can accomplish full depth recycling with a high degree of precision and economy.

Recycling Portland Cement Concrete Pavements

Existing deteriorated concrete pavement can be reused as a base for a bituminous overlay by cracking and seating or fracturing and resurfacing. Cracking and seating relieves the stresses and faulting of large pavement slabs by cracking the pavement into smaller slabs prior to resurfacing. Fracturing and resurfacing creates an aggregate base by fracturing the concrete pavement into rubble-sized fragments and then resurfacing.

The Bureau of Local Roads and Streets is offering a seminar on pavement recycling as a part of the Local Roads Training Program. The seminar will have experts from the Department and the construction industry talking about methods and economics of various approaches to pavement recycling. The seminar will be presented in Glen Ellyn, Illinois on November 24th; Peoria, Illinois, on December 1st and Mount Vernon, Illinois, on December 8th. For additional information about the recycling seminar, contact: Mr. W. B. Ross, Illinois Department of Transportation, 2300 So. Dirksen Parkway, Room 205, Springfield, Illinois 62764,217-782-0689. •

Page 4 / Illinois Municipal Review / November 1987