SOME THOUGHTS ON HOW TO AVOID "FRETTING" OF BITUMINOUS MATERIALS

This paper describes the development of a theory of fretting from a study of actual road failures and results from laboratory tests which examined many of the factors affecting resistance to fretting. Fretting is concerned with the loss in strength of the finer mortar and subsequent loss of mortar from the aggregate skeleton itself. It can be caused by inadequate initial compaction, inadequate secondary compaction by traffic or by paving during wet or cold weather. The laboratory programme used to validate the failure theory was based on the TRRL immersion test. Using the test it was possible to distinguish three stages of failure: 1) loss of internal mix stability, 2) complete loss of fines cohesion and 3) mix stripping and the weakening of mortar. It was found that rolled asphalt materials have a greater resistance to fretting than macadams; dense bitumen macadams are more sensitive to failure than open textured macadams. Suggestions are given of how significant improvements can be made by better compaction. The use of good quality materials, laying thicker layers and avoiding bad weather can also improve the resistance to fretting. (Author/TRRL)

• Corporate Authors:

  INSTITUTE OF ASPHALT TECHNOLOGY

  PAPER MEWS PLACE, 290 HIGH STREET
  DORKING, SURREY  United Kingdom  RH4 1QT

  INSTITUTE OF ASPHALT TECHNOLOGY

  PAPER MEWS PLACE, 290 HIGH STREET
  DORKING, SURREY  United Kingdom  RH4 1QT
• Authors:
  • Pooley, G
  • Page, N
• Publication Date: 1982-8

Media Info

• Features: Figures; Photos; Tables;
• Pagination: p. 24-27
• Serial:
  • Asphalt Technology
  • Issue Number: 32
  • Publisher: INSTITUTE OF ASPHALT TECHNOLOGY

Subject/Index Terms

• TRT Terms: Bituminous materials; Bituminous mixtures; Cohesion; Compaction; Defects; Failure; Fines (Materials); Flexible pavements; Loss and damage; Losses; Macadam; Mortar; Prevention; Rolled asphalt; Stability (Mechanics); Strength of materials; Stripping (Pavements); Temperature; Tests; Water
• Uncontrolled Terms: Laying
• Old TRIS Terms: Fretting
• ITRD Terms: 4955: Bituminous materials; 4967: Bituminous mixture; 3686: Compaction; 5238: Defect (tech); 5520: Failure; 9023: Fine (mater); 2944: Flexible pavement; 3623: Laying; 9040: Loss; 4769: Mortar; 5930: Stability; 5544: Strength (mater); 6722: Temperature; 6255: Test; 4355: Water
• Subject Areas: Highways; Materials; Security and Emergencies; I31: Bituminous Binders and Materials;

Filing Info

• Accession Number: 00373521
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Jul 30 1983 12:00AM