University of California Institute of Transportation Studies

Determining where trucks are traveling is crucial for planning and maintaining transportation networks. In California, information about truck movements is primarily derived from a network of fixed monitoring stations. These include weigh-in-motion stations (truck scales) and traffic count stations. Information from these locations can be used to classify passing trucks (light, medium, or heavy-duty), determine their travel direction, and estimate their proportion of the general traffic; however, the data provides limited information about trip origins and destinations and the routes taken in between stations. Estimating truck movements within a region thus largely depends on extrapolating data between known collection points. While this can be done with relative ease in simple networks containing few alternate routes, it can be a difficult task in complex networks without significantly increasing the number of fixed monitoring stations.