摘要: |
Comprehensive traffic loading data are essential for planning, designing, and maintaining highway systems. Two augmented weigh-in-motion (WIM) systems have been installed in the southbound lanes of US-59 in east Texas for the purpose of collecting and analyzing traffic data. An augmented WIM system is composed of an inductance loop detector, a weighpad in each wheel path, an infrared sensor unit for each lane, and two thermocouples. The weighpads in each lane are staggered longitudinally to measure speed and distance between axles in addition to wheel weights. The infrared sensors are set up in such a way that an infrared light beam passes just above the pavement surface. This light beam is blocked by the outside tires of vehicles traversing the weighpads. The lateral position of the tires can be determined and single or dual tires can be indicated. The two thermocouples measure the air and pavement temperatures hourly. Traffic data were collected continuously throughout 1993. Speed, volume, equivalent single-axle loads, lateral position, and temperature data were analyzed to find weekly and monthly trends. The data analysis is also organized by vehicle class and by lane. |