Expanding Portable B-WIM Technology

Advances in weigh-in-motion (WIM) technology over the past 15 years have led to successful field application of a commercial grade portable Bridge WIM system (B-WIM) in Europe. Under a previous UTCA Research Project No. 07212, the University Transportation Center for Alabama (UTCA) tested the state-of-the-art commercially available B-WIM technology on two interstate highway bridges. The equipment tested was developed by CESTEL, a Slovenian technology company, and is commercially referred to as the SiWIM system. Some technical difficulties occurred during the Project 07212 field tests; however, the SiWIM system was successfully installed, calibrated, and placed into a data gathering mode at both sites. The objective of the research described in this report was to develop a practical recommendation for installation of SiWIM technology at potentially multiple locations in the State of Alabama for the primary purpose of traffic enforcement. The researchers worked with the Alabama Department of Transportation (ALDOT) to select a bridge for instrumentation that has the potential for an excellent accuracy classification rating. The bridge selected is located on US Highway 78 East in Graysville, Alabama. The bridge structure consists of three 42-ft simply supported reinforced concrete T-beam spans with two traffic lanes in one direction. In addition, an ALDOT-operated Bending Plate Weigh-In-Motion System (BP-WIM) is located approximately four miles to the west also on US Highway 78. After installing the SiWiM system on the bridge, calibration and three in-service simulated enforcement test exercises were conducted. Over one hundred trucks were weighed by the SiWIM system and compared to their static weights. Many of the trucks were also weighed by the BP-WIM system. The accuracy classification established for the SiWIM system during the calibration and subsequent in-service tests varied between ±20% and ±44% of the static weight with a confidence level of 85%. This level of accuracy is not precise enough to be used with confidence to screen trucks for weight enforcement. The additional BP-WIM data collected during this program indicated that the SiWIM system may be as accurate as the nearby BP-WIM system tested. Lessons learned from the work reported here have been of benefit. In March, 2011, ALDOT personnel installed, calibrated, and operated a newer model of the SiWIM system on a shorter span bridge, achieving B(10), C(15), AND B(10) accuracy classification in random truck weighing for gross vehicle weight, group axles, and single axles, respectively.

• Record URL:
  http://utca.eng.ua.edu/research/projects/?id=08204
• 
• Supplemental Notes:
  • This research was sponsored by the U.S. Department of Transportation, University Transportation Centers Program.
• Corporate Authors:

  University of Alabama, Birmingham

  Department of Civil, Construction and Environmental Engineering
  1075 13th Street South
  Birmingham, AL  United States  35294

  University Transportation Center for Alabama

  University of Alabama
  Tuscaloosa, AL  United States  35487

  Research and Innovative Technology Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Hitchcock, Wilbur A
  • Toutanji, Houssam
  • Richardson, James
  • Salama, Talat
  • Callahan, Dale
  • Jackson, Joshua
  • Zhao, Hua
• Publication Date: 2011-6-28

Language

• English

Media Info

• Media Type: Web
• Features: Figures; Photos; References; Tables;
• Pagination: 56p

Subject/Index Terms

• TRT Terms: Accuracy; Calibration; Field tests; Gross vehicle weight; Highway bridges; Portable equipment; Traffic law enforcement; Weigh in motion
• Geographic Terms: Alabama
• Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;

Filing Info

• Accession Number: 01351430
• Record Type: Publication
• Report/Paper Numbers: UTCA Report Number 08204
• Files: UTC, TRIS, USDOT
• Created Date: Sep 9 2011 3:08PM