MICRODAMAGE HEALING IN ASPHALT AND ASPHALT CONCRETE, VOLUME III: A MICROMECHANICS FRACTURE AND HEALING MODEL FOR ASPHALT CONCRETE

Volume III documents the development of a micromechanics fracture and healing model for asphalt concrete. This model can be used to calculate the density and growth of microcracks during repeated direct tensile controlled-strain loading. The model is based on a relationship among stiffness changes in the mixture as damage occurs, the rate of change in dissipated pseudo strain energy as loading is applied to the samples and as damage occurs, and mixture properties including crack length changes upon loading and mixture cohesive surface energies. The report demonstrates that microcrack growth is the dominate mode of distress at temperatures below 25 deg C and that microcrack healing is the dominate mode of recovery of dissipated pseudo strain energy at these test temperatures. However, at temperatures above about 25 deg C, the predominate mode of distress is plastic damage. Cracking rates during fatigue damage are related to de-wetting cohesive surface energy measurements of the bitumen whereas microcracking healing rates are related to wetting cohesive surface energy measurements of the bitumen. Surface energies of five bitumens with widely different chemical compositions were found to correlate strongly with healing properties as defined by viscoelastic fracture and healing theory.

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• Record URL:
  https://rosap.ntl.bts.gov/view/dot/15432
• Record URL:
  https://rosap.ntl.bts.gov/view/dot/25328
• Supplemental Notes:
  • Research Project Title: Fundamental Properties of Asphalts and Modified Asphalts, Task K - Microdamage Healing in Asphalt and Asphalt Concrete.
• Corporate Authors:

  Texas Transportation Institute

  Texas A&M University System, 1600 E Lamar Boulevard
  Arlington, TX  United States  76011

  Western Research Institute

  365 North 9th Street
  Laramie, WY  United States  82072-3380

  Federal Highway Administration

  Turner-Fairbank Highway Research Center, 6300 Georgetown Pike
  McLean, VA  United States  22101
• Authors:
  • Lytton, R L
  • Chen, C W
  • Little, D N
• Publication Date: 2001-6

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: 78 p.

Subject/Index Terms

• TRT Terms: Asphalt concrete pavements; Asphalt pavements; Mathematical models; Microcracking; Surface energy; Temperature
• Uncontrolled Terms: Microdamage healing; Viscoelastic fracture
• Subject Areas: Design; Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I23: Properties of Road Surfaces; I31: Bituminous Binders and Materials;

Filing Info

• Accession Number: 00815747
• Record Type: Publication
• Report/Paper Numbers: FHWA-RD-98-143,, Research Report 7229
• Contract Numbers: DTFH61-92-C-00170
• Files: NTL, TRIS, USDOT
• Created Date: Aug 6 2001 12:00AM