COMPACTION CONTROL OF BITUMINOUS CONCRETE USING NUCLEAR DENSITY GAUGES. FINAL REPORT

The objective of this study was to develop a procedure for the use of the thin layer nuclear density gauge by collecting data from the laboratory and field. An analysis of the laboratory data showed that there was no significant difference in the averages of four readings taken at one, two, or four minute counts. Also, it was observed that the influence of the density of the underlying material on the top layer density determination is a function of top layer thickness. Field data were collected during the 1987 and 1988 construction seasons. In 1987, data were collected using the normal, special calibration, and surface void modes. Analysis of the 1987 data showed that the mean of the nuclear densities obtained using the special calibration mode were the same as the mean core densities. Therefore, in 1988 data were collected using the special calibration mode only. A 95% confidence interval for the difference between the core density and nuclear special calibration density was found to be 1 pcf for 46% of the projects, 1.5 for 40% of the projects, and 2 pcf for 14% of the projects. Using a 95% confidence interval, the 1987 data were reasonably close to the 1988 data.

Language

  • English

Media Info

  • Features: Appendices; Figures; Tables;
  • Pagination: 187 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00624984
  • Record Type: Publication
  • Report/Paper Numbers: FHWA/MD-89/02
  • Contract Numbers: AW089-316-046
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: Sep 22 1993 12:00AM