Temperature Predictions and Adjustment Factors for Asphalt Pavement
Primary Topic: Pavement Maintenance
Description: This report presents the results of an analysis of the response that deflections and backcalculated asphalt moduli have to the pavement temperature. The study used deflection and temperature data from 40 sites monitored in the Seasonal Monitoring Program of the Long-Term Pavement Performance (LTPP) program. The LTPP Guide to Asphalt Temperature Prediction and Correction is based on this report.
The report presents improved methods of estimating the temperature within an asphalt pavement based on the measurement procedures used for the LTPP program. The data necessary to estimate the temperature within the asphalt included the surface temperature, time of day, depth below the surface, and the average air temperature from the previous day. Backcalculation of the asphalt modulus from the deflection data of the 40 sites was related to pavement temperature, and a method of estimating what the modulus of the asphalt would be at different temperatures is presented. Deflection and deflection basin shape factor response to temperature was also evaluated, resulting in relationships for each of the items evaluated with pavement temperature. Items evaluated include the deflection under the load plate (center sensor), center sensor minus offset sensors, center sensor divided by offset sensors, AREA factor, and the F-1 factor. The relationships were then used to develop procedures for adjusting for the effects of temperature.
FHWA Publication Number: FHWA-RD-98-085
Publication Year: 2000