Investigation of the Effect of Weight Factor on Performance of Piezoelectric Weigh-in-Motion Sensors

Trucking industry growth increases loads on existing roads and may raise the possibility of overloaded vehicles, which consequently cause significant damage to pavement. Weigh-in-motion (WIM) technology improves weight enforcement activities by increasing the capacity of static weigh stations and provides traffic monitoring and traffic data for pavement research and design. However, there is still a lack of knowledge about the behavior of WIM sensors installed in different environments, which affects reliable and precise data gathering. Therefore, different types of piezoelectric WIM systems, including quartz, polymer, and ceramic sensors, were installed at the Center for Pavement and Transportation Technology (CPATT) test sites of the University of Waterloo in Canada. The objective of this research is to explore the behavior of piezoelectric WIM sensors under different load conditions specifically for the polarized sensors, which illustrated heteroscedasticity in weight estimations caused by inconsistent variance of estimations. The issue was solved by transformation of variables, which resulted in constructing a compensation curve. The investigated effect of the weight factor will assist in the recommendation of improved benefits of the least expensive WIM technology.