Successful Practices in Weigh‐in‐Motion Data Quality with WIM Guidebook, Volume 1

The Arizona Department of Transportation (ADOT) plans to install new weigh‐in‐motion (WIM) stations with either piezo-polymer or piezo-quartz sensors. Recognizing some limitations of WIM sensor technologies, ADOT sponsored this study to ensure the accuracy of the future WIM data collection. The project tasks included (1) reviewing other highway agencies’ practices related to WIM data quality assurance through literature review and a survey; (2) developing a guidebook of clear recommendations for managing WIM installation, calibration, maintenance, and data quality assurance; and (3) developing a research report with recommendations on how to achieve successful implementation of a WIM program. Through reviewing available literature and surveying selected highway agencies, the project team determined that the piezo-quartz sensors perform much better than the piezo-polymer sensors due to their consistent reliability, reduced calibration requirements, and relative temperature insensitivity. With proper installation, piezo-quartz WIM sensors should provide accurate axle and truck weight measurements in Arizona. Findings also indicated that piezo-polymer sensors should perform well in Arizona for vehicle classification, traffic volume, and speed studies, but not for weight data collection. This is due to the temperature sensitivity of piezo-polymer sensors and to the limitations of auto-calibration and temperature compensation technologies in environments where pavements undergo rapid day-to-night temperature changes and are subjected to high seasonal temperatures. Piezo-polymer sensor use with an auto-calibration feature for weight measurements should be evaluated on a case-by-case basis. Using findings from the literature review and the successful WIM practices survey, the research team developed a guidebook with recommendations and procedures for WIM site selection and qualification, installation, calibration, maintenance, data quality assurance, and personnel needed to support ADOT’s WIM program. These recommendations are specific to WIM systems that use piezo-quartz sensors and piezo-polymer sensors. The guidebook is included as Chapter 4 of this final report (Volume 1). The final report appendices are contained in a separate volume, Volume 2.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 162p

Subject/Index Terms

Filing Info

  • Accession Number: 01673694
  • Record Type: Publication
  • Report/Paper Numbers: FHWA-AZ-17-731
  • Contract Numbers: SPR-000 1(184) 731
  • Created Date: Jun 21 2018 10:05AM