Check Post Management and WIM Systems

Weigh-in-motion (WIM) scales are installed on various higher order roads to provide traffic loading information for pavement design, strategic planning and law enforcement. Some WIM systems produce anomalies that cannot be satisfactorily explained even by highly experienced professionals.Much of the problem relates to the difficulty in determining the appropriate calibration factors to correct systematic measurement

error for WIM systems and the inadequacy of data quality management methods.The author has developed a post-calibration method for WIM data, called the Truck Tractor (TT) method, to correct the magnitude of recorded axle loads in retrospect. In addition, it incorporates a series of data quality checks. The TT method is robust, accurate and adequately simple for use on a routine basis for a wide variety of WIM systems.

Weigh-in-motion (WIM) scales are installed on various higher order roads to provide traffic loading information for pavement design, strategic planning and law enforcement. Large sums of money are spent annually on WIM data collection, yet the data collected are often inconsistent and the pavement loading characteristics that are derived are not always realistic.

Some WIM systems produce anomalies that cannot be satisfactorily explained even by highly experienced professionals. Consequently, there is still no consensus within the industry on the physical requirements for a WIM system, the calibration of WIM data and the data quality checks that can be used to manage contractor performance and identify or eliminate erroneous or dubious weigh records. Agencies and WIM vendors across the world are still experimenting with variations (and often simplifications) of the two most respected WIM guidelines, the American ASTM E1318 Standard (ASTM International 2002) and the COST 323 European Specification (COST 323 1999), yet enhancements contributed by researchers are often highly complex and consequently under-utilised in practice.