LOW TEMPERATURE CRACKING OF MODIFIED AC MIXES IN ALASKA. VOLUME I: FINAL REPORT; VOLUME II: APPENDIX A; AND VOLUME III: APPENDICES B-H

Low temperature cracking is a major distress mode in Alaskan pavements due to the extreme temperature conditions that range, in some instances, from about -50 deg C in winter to 40 deg C in summer. The use of asphalt modifiers in Alaskan pavements occurred over the past 15 years. These modifiers include SBR polymers, SBS polymers, ULTRAPAVE and CRM (both the dry process, PlusRide, and the wet process). Field observations and laboratory studies in Alaska and elsewhere, indicate that the use of these modifiers would improve the low temperature cracking resistance of pavements. The degree these modifiers provide for Alaskan pavements needs to be evaluated. The objectives of this research were: 1) To characterize asphalt and polymer modified asphalt mixes from a number of selected sites using Strategic Highway Research Program (SHRP) Superpave PG grading system, thermal stress restrained specimen test (TSRST), and Superpave IDT laboratory tests on field specimens; 2) To compare low temperature cracking performance using field surveys; 3) To verify the applicability of SHRP Superpave thermal cracking; and 4) To assess the preliminary economic benefits from using polymer modified asphalts. Results of this study indicate in general significant improvement in the low temperature cracking resistance when polymer modifiers are used. The corresponding reduction in crack sealing costs are estimated to be between 30% and 40%. Minimum air and pavement temperature correlations were developed using field data covering Alaska's climatic zones. Contour maps for Alaskan roads corresponding to 50% and 98% reliability minimum pavement temperature were developed. Design recommendations to minimize low temperature cracking and estimate crack progression with age were established.

• Supplemental Notes:
  • Volume I contains 164 pages. The other two volumes are each slightly larger than Volume I.
• Corporate Authors:

  University of Alaska, Fairbanks

  Institute of Northern Engineering, P.O. Box 755910
  Fairbanks, AK  United States  99775-5900

  Alaska Department of Transportation and Public Facilities

  3132 Channel Drive
  Juneau, AK  United States  99801-7898

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Raad, L
  • Saboundjian, S
  • Sebaaly, P
  • Epps, J
  • Camilli, B
  • Bush, D
• Publication Date: 1997-3

Language

• English

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: v.p.

Subject/Index Terms

• TRT Terms: Asphalt rubber; Atmospheric temperature; Contour maps; Economic benefits; Field studies; Laboratory tests; Low temperature; Pavement cracking; Polymer asphalt; Superpave; Surface temperature
• Geographic Terms: Alaska
• Subject Areas: Design; Economics; Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I23: Properties of Road Surfaces; I31: Bituminous Binders and Materials;

Filing Info

• Accession Number: 00764624
• Record Type: Publication
• Report/Paper Numbers: INE/TRC 97.05,, SPR-95-14,, Final Report
• Files: TRIS, USDOT, STATEDOT
• Created Date: Jun 3 1999 12:00AM