Phillips Petroleum has proven that paving fabrics can be recycled when incorporated with hot mix asphalt concrete (HMAC). The current view of recycling HMAC with paving fabric is that it is a difficult process – this is only true if the paving fabric is placed improperly or if improper recycling methods are used.
The current process of installing paving fabric has improved with knowledgeable agencies, contractors and fabric installers by using improved computer rate controlled distributor trucks to apply the fabric binder. This is done to insure the proper amount of performance graded (PG) asphalt binder is being placed to obtain the waterproofing benefit of the installed paving fabric and to insure enough binder is also present to allow adhesion of the HMAC resurfacing to the paving fabric and to the underlying pavement.
Milling a HMAC pavement with a paving fabric interlayer present can be done if the appropriate milling equipment and technique is used. Milled HMAC with paving fabric can be processed through asphalt plants and recyclers that have the resources to effectively process these milled materials - these facilities are able to process these milled materials in large quantities. To successfully recycle conventional paving fabrics:
- Apply the proper amount of PG asphalt binder when placing paving fabric to insure adhesion of the HMAC to the paving fabric, and the paving fabric to the underlying pavement
- Use appropriate milling equipment and milling techniques
- Process milled material through asphalt plants or recyclers properly equipped to process properly milled HMAC with paving fabric
Green paving fabrics will give some improvement over conventional paving fabrics because of its blended construction. The increased amount of PG asphalt binder retained and its manufacturing with the resin from post-consumer plastic, will be a benefit in its recyclability.