One technique commonly used in the rehabilitation of roads, highways, and airport runways is cold planning (CP). Cold planning is the controlled removal of an existing pavement to the desired depth, longitudinal profile, and cross-slope, using specifically designed equipment. Cold planning can also be used to remove deteriorated, cracked, aged asphalt pavement, or pavement that is unacceptable for other reasons.
The modern cold planer or milling machine has a large diameter rotary cutting drum or “cutter/rotor/mandrel” housed in its cutting chamber. The cutter is equipped with specially designed replaceable tungsten carbide cutting teeth that remove or mill the existing pavement.
Water is used during the milling operation to control the amount of dust generated and to extend the life of the cutting tools. The water is sprayed onto the tools by a series of spray nozzles that cover the width of the cutting chamber. Milling machines are self-propelled and are a sufficient size to provide the traction and stability required to remove the pavement surface to the specified grade and cross-slope. Machines are equipped with automatic grade and slope control systems to produce results to your specified elevations and grades.
Reclaimed asphalt pavement generated during the cold planning process is loaded onto haul trucks by a conveyor system on the milling machine and typically is removed from the site.