The data are used to assess the longevity and performance of a pavement and determine which pavement construction methods are most effective. The conference will include sessions on such topics as using global positioning system and cellular technology for traffic and travel monitoring, building intelligent transportation system data archives, and analyzing and using traffic data. The SPS experiments were designed to learn how such factors as cumulative traffic loading affect pavements of different compositions, environmental conditions, and layer thicknesses. However, at some of the sites, traffic data collection has been inadequate. Larry Wiser of FHWA's LTPP program will discuss the plans being considered by the ETG and the LTPP program.
Smoother pavements provide more accurate and less variable measurements.
To ensure that WIM equipment is installed in smooth pavements, and to achieve more uniform conditions among different SPS test sites, criteria have been developed to help a State evaluate the pavement both at the time of construction and while it is in service. In a related presentation, Barbara Ostrom, a contractor to FHWA, will discuss WIM equipment selection and installation for SPS sites. Until now, traffic data collection at SPS sites has not been conducted using identical WIM equipment at all locations. In consultation with the Traffic ETG, FHWA's LTPP team has developed specifications for WIM systems that include accuracy requirements and construction guidelines.