FREE TRAINING FEATURE

FREE TRAINING FEATURE

Want to learn more about pavement management, in-place recycling, and pavement preservation? Do you feel like you're setup for failure as an agency engineer with little or no money to spend on your roads? Enter your email below to get free instant access to a two-hour video-training session that Blair did for the Northwest Pavement Management Association:

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Blair Barnhardt

Cold Recycling

Cold Recycling (CR) consists of recycling asphalt pavement without the application of heat during the recycling process to produce a rehabilitated pavement.  Cold Recycling is a method of reconstructing any flexible pavement where the need arises from structural failures.  These failures include: transverse cracking wheel rutting, potholes, surface irregularities, or a combination of the above.  The two distinct sub-categories within CR are Cold In-place Recycling (CIR) and Cold Central Plant Recycling (CCPR).

When Blair Barnhardt teaches the 2 day workshop on asphalt recycling, he makes it clear the the students that Cold In-place Recycling involves partial depth removal of the existing asphalt pavement.  The material that is removed is mixed with a bituminous agent such as emulsion or foamed asphalt cement and placed back down and compacted like regular hot mix asphalt pavement.

Cold In-Place Recycling (CIR):

CIR is the on-site recycling process to a typical treatment depth of 2 to 5 inches, using a train of equipment (tanker trucks, milling machines, crushing and screening units, mixers, pavers, and rollers), an additive or combination of additives (asphalt emulsions, rejuvenating agents, lime, fly ash, cement), generating and re-using 100% RAP, with the resulting recycled pavement usually opened to traffic at the end of the work day.

While plenty of information is available through The Barnhardt Group or otherwise, it is important to know there are three distinct configurations of the Cold In-place Recycling train.  They are:

  • Single-Unit Train
  • Dual-Unit Train
  • Multi-Unit Train

Further, its important for the owner agency to understand that the Cold In-place recycled mat acts as the binder base course and must be overlaid with the wearing course such as slurry, Micro-Surfacing, or hot-mix asphalt (HMA) pavement.

For the most part, an agency candidate for CIR should have a minimum of 4″-5″ of asphalt in-place before rehabilitation.  It is also important to note, that because of the size of the equipment and the limited number of contractors performing this work in America,  the minimum job size should be 50,000 square yards.

Cold Central Plant Recycling (CCPR):

For owner agencies that may find themselves 40 or 50 miles away from the nearest hot-mix plant, CCPR provides a viable option for reconstruction.  For example, a remote agency may have a large stockpile of recycled asphalt product (RAP) millings.  A CCPR plant can be mobilized to this site to mix the stockpiled RAP with an emulsion or foamed asphalt stabilizing agent.  From the stockpile location, this cold recycled asphalt may be trucked locally to the job site and laid down with conventional paving and compaction equipment.  Refer to the images below and for more information contact The Barnhardt Group.

Single-Unit Train

CIR Single-Unit Train

CIR Dual-Unit Train

CIR Dual-Unit Train

CIR Multi-Unit Train

CIR Multi-Unit Train

Recycling a typical road

Recycling a typical road

Central Foamed Asphalt or Emulsion Plant

Central Foamed Asphalt or Emulsion Plant

Easy mobilization for central plant

Easy mobilization for central plant