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

Hot Recycling

Hot recycling is a proven technology that provides a timely answer to the nation’s road maintenance and rehabilitation problems.  Successfully completed projects across the country have shown both cost effectiveness and quality of pavement produced by this time-tested process.  Reclaimed aggregates and asphaltic cements are broken down to their original state and reused to produce high quality asphaltic concrete, the performance of which has been proven to equal that of conventional mixes.

Hot recycling can transform old, deficient pavements into good functional roadways.  Problems associated with deterioration of asphalt and gradation can be corrected with aggregates and asphalt added to the new mix.  Hot recycling can also help correct and maintain vertical and horizontal geometrics.  Where curb and bridge clearances are affected, old overlays can be milled and recycled in a coast effective rehabilitation alternative.

In addition to these pluses, hot recycling:

  • Eliminates the disposal problems inherent in conventional methods
  • Requires only minor modifications to existing equipment
  • Can be performed in compliance with existing air pollution control standards
  • Can be done repeatedly using the same materials

Asphalt is the number one recycled product in America.  We take up and recycle almost a fifth of the material that has been placed on the ground over the years.  Ideally, the recycled asphalt product (RAP) is milled the existing road base with a cold milling machine, transported back to the hot-mixed asphalt plant, and then crushed and sized into two distinct fractions, coarse and fine (see pictures below).  Optimum storage would involved an overhead canopy to keep moisture out of the crushed and sized aggregate.  With modern technology, up to 50% of RAP may be incorporated into a new hot-mix binder asphalt.

Photos:

Coarse Fraction RAP (Recycled Asphalt Product)

Coarse Fraction RAP (Recycled Asphalt Product)

Fine Fraction of RAP after processing

Fine Fraction of RAP after processing

Processing RAP into two different sizes

Processing RAP into two different sizes

Typical hot asphalt recycling drum plant silos and RAP stockpile

Typical hot asphalt recycling drum plant silos and RAP stockpile