A framework for monitoring asphalt mix temperature during construction using Statistical Process Control charts

Current quality control mechanisms tend to focus on the end-result and not on elements of the asphalt construction process that may lead to an asphalt layer not lasting for its intended life. Specifications tend to focus on quality characteristics, some of which are the percentage voids, the final density and layer thickness of the compacted mix. Statistical testing in its current form provides vital indications of whether the contractor has complied with the quality requirements set by the client. While statistical testing is relevant and important, it does not provide significant insight into the overall risk of failure because of “processes gone wrong." The missing link is a focus on the process, and whether there is variability in the construction process. This paper presents a framework for monitoring asphalt mix temperature during construction using Statistical Process Control (SPC) techniques. The techniques are applied to more than 40 asphalt construction projects in the Netherlands where new technologies including Differential GPS, infrared cameras and laser linescanners are used to monitor and make the construction process explicit. Most projects show evidence of extensive temperature homogeneity with large temperature differentials due to assignable causes of variability at the asphalt plant, during transport or on the construction site. These operational problems are in the main, causing the construction process to be “out of control” and possibly could have been avoided with better planning. Overall, this research shows that acceptance testing, on its own, does not holistically capture the extent of variability encountered in the asphalt process. The absence of a record of the process is a significant gap in fully understanding the most important process parameters.

Language

  • English

Media Info

  • Pagination: 9p
  • Monograph Title: 11th Conference on Asphalt Pavements for Southern Africa: CAPSA15, 16-19 August 2015, Sun City, South Africa

Subject/Index Terms

Filing Info

  • Accession Number: 01597075
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ATRI
  • Created Date: Apr 22 2016 11:12AM