This study evaluated the applicability, durability, and accuracy of two general systems of sensors that were used to monitor truck speeds on a freeway connector: 1) pavement sensors mounted on the surface or submerged into the pavement, and 2) roadside sensors using an infrared beam technology. Pavement sensors were predominantly temporary piezoelectric sensors, although inductive loops complemented one set of piezo sensors. These pavement sensors generated signals that were processed by vehicle classifiers to produce either "binned" data or "raw" data for all vehicles using the monitored roadway. Roadside sensors monitored vehicles that exceeded a preset height, length, and speed. Findings indicate that temporary piezo sensors are accurate for use as speed, count, and classification studies, but their service life (durability) was highly variable and undesirably short in many cases. Installation and maintenance of these sensors were problematic due to interference with traffic. Infrared sensors, on the other hand, were less intrusive to the traffic stream during installation and maintenance, and they performed well with little maintenance for time periods of one year or longer.

  • Supplemental Notes:
    • Research study title: Urban Highway Operations Research and Implementation Program.
  • Corporate Authors:

    Texas Transportation Institute

    Texas A&M University System, 1600 E Lamar Boulevard
    Arlington, TX  United States  76011

    Texas Department of Transportation

    Research and Technology Transfer Office, P.O. Box 5051
    Austin, TX  United States  78763-5051

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Middleton, D R
  • Publication Date: 1993-11


  • English

Media Info

  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 60 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00662900
  • Record Type: Publication
  • Report/Paper Numbers: FHWA/TX-93/1232-21, Res Rept 1232-21, TTI: 0-1232
  • Contract Numbers: Study 0-1232
  • Created Date: Jul 22 1994 12:00AM