Pilot Project Instructions for Use of Long Life Asphalt Standard Special Provisions

The pilot special provisionsare meant to be used alone or in parts depending on the project. Long Life Asphalt can be used on wearing course overlay projects, binder and wearing course overlay projects, and full depth asphalt projects. The following guidelines are split into these three project types. All asphalt mixes may be either warm mix or hot mix asphalt.

Wearing Course Overlay Projects:

  • Use only on interstateand interstate look alike paving projects.
  • Use only on projects with stable base conditions.
  • Use only for main line paving. Do not use for shoulders, temporary pavement, miscellaneous areas, etc.
  • Use on projects with a minimum of 100,000square yards of wearing course designated as Long Life Asphalt.
  • Specify a 9.5mm HMA, or WMA scratch course that complieswith the roadway design ESALs used for the wearing course as needed.
  • Include an item for Section 405 Evaluation of Bituminous Pavement Longitudinal Joint Density and Payment of Incentive / Disincentive.
  • Include an item for Section 404 Evaluation of Bituminous Pavement Ride Quality and Payment Incentive.
  • Include quantities of Bituminous Tack Coat Section 460, to cover the application of tack between each pavement course.
  • This specification includes possible incentivesof 2% for SMA wearing course density, longitudinal joint density incentives of $5000.00per 2500 feet of joint, and a ride incentive of a possible $600.00 per lot. Districts should ensure that they have budgeted for all 3 of these possible cost incentive increases.
  • Comply with all other requirements of Publication 242.
  • Note the use of the Long Life Asphalt special provision on the Pavement Type Approval Form D-4332.

Binder and Wearing Course Overlay Projects: All of the bullet points for Wearing Course Overlay Projects withthe following additions and modifications.

  • The binder layer includes a Percent Within Limits acceptance specification that includes a possible incentive payment of 4%. Districts should ensure that they have budgeted for these possible cost incentive increases.
  • Districts need to decide, based on the traffic and service level, if there is a high enough rutting potential to warrant the use of a polymer modified asphalt in the binder layer. The use of a polymer asphalt in the binder is recommended for roadways over 2,500 ESALs per day but should be considered for roadways over 1500 ESALs per day in areas where hills or traffic conditions slow traffic below 45 miles per hour frequently.

Full Depth Asphalt Projects: All of the bullet points for Binder and Wearing Course Overlay Projects with the following additions and modifications.

  • In accordance with AASHTO R 35,Section 8.3, note 9, specify base layers that are not asphalt rich base layers one ESAL level lower than the design traffic ESAL level unless the mixture will be exposed to significant mainline construction traffic prior to being overlaid.
  • For base courses placed in multiple lifts, (25 mm > 6 inches, 37.5 mm > 8 inches) specify the bottom layer as an Asphalt Rich Base Course.Specify Asphalt Rich Base Courses for bottom base layers only.Asphalt Rich Base courses are limited to a minimum depth of 3 inches and a maximum depth of 4 inches.
  • In accordance with AASHTO R 35, Section 8.3, note 9, specify base layers that are Asphalt Rich Base layers one ESAL level lower than the design traffic ESAL level. (in no case should the Ndesign level be greater than 75 gyrations)
  • For full depth paving projects, use on projects with a minimum of 60,000 square yards of wearing course designated as Long Life Asphalt.
  • The Asphalt rich base layer includes a Percent Within Limits acceptance specification that includes a possible incentive payment of 4%. Districts should ensure that they have budgeted for these possible cost incentive increases.