LTPP Data Collection

The Long-Term Pavement Performance (LTPP) program monitors more than 2,500 asphalt and portland cement concrete (PCC) pavement test sections throughout the United States and Canada. A total of 934 LTPP test sections contain the common types of pavement in use in the United States (General Pavement Studies, GPS), and 1,580 other test sections have been specially constructed to study certain engineering factors in pavement design (Specific Pavement Studies, SPS). At each GPS and SPS site, data on distress, roughness, structural capacity, traffic, and other variables are systematically collected. In addition, work groups of highway engineers periodically visit the sites to get a firsthand look at the pavements and to record their subjective observations.

Selected sites within the GPS and SPS experiments were continuously monitored for temperature and moisture as part of the Seasonal Monitoring Program (SMP) study. For the Dynamic Load Response study, various PCC sections within the SPS-2 project were chosen for a study on pavement response under controlled loading conditions.

Management Process and Monitoring Schedule

Data collection and management are core functions of the LTPP program. They are also a shared function between the program and the States and Provinces. Up until the mid-2000s, the program maintained four LTPP regional offices—North Atlantic, North Central, Southern, and Western—to coordinate the data collection and management activities. The LTPP program still maintains these four regions (Figure 1), but data collection is now being conducted by a single contractor. For information on LTPP data collection including test sections visit LTPP InfoPave™. To see the monitoring schedule and data collection contact information, please visit the Operations hub of the web portal.

Figure 1. The four LTPP regions.