PFC should be considered for use only on structurally sound pavements. If placed on badly cracked pavements, the cracks will reflect through the PFC in a short period of time. Based on field observations and laboratory analysis of field data, a gradation can be recommended that will result in a good long-term permeability performance. A mix design procedure utilizing the relationship 2 K sub c + 4 to estimate bitumen content can be used with confidence. Both laboratory tests and field performance have verified this confidence. It is recommended that a temperature-viscosity relationship be developed over a reasonable range of mixing temperatures for the job bitumen. With this relationship, the mixing temperature can be chosen based on a mixing viscosity of 275 plus or minus 25 centistokes. This viscosity mixing range has been verified by prototype field construction conditions. Utilizing the recommended gradation surface constant relationship for obtaining a bitumen content and the temperature-viscosity relationship for choosing a mixing temperature, a PFC can be constructed with confidence where good construction quality control procedures are applied. If it is desired to verify bitumen drainage characteristics, the bitumen drainage test can be conducted utilizing a 2-hour conditioning time at a temperature giving a viscosity of 275 centistokes. In addition, laboratory water permeability can be determined for the job PFC mix by preparing laboratory samples consisting of a 3/4-in. PFC cap on a dense 6-in.-diam base core where the PFC mix is compacted with 10 blows of the Marshall hand hammer with a 6-in.-diam steel foot.

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 136-160

Subject/Index Terms

Filing Info

  • Accession Number: 00163671
  • Record Type: Publication
  • Report/Paper Numbers: S.C.W. Record 2 Proceeding
  • Files: TRIS
  • Created Date: Mar 14 1978 12:00AM