Field monitoring and comparison of thermal- and load-induced strains in asphalt pavement

The influence of pavement temperature variations on field thermal-induced strains has not been well studied. Measuring the thermal- and load-induced strains in field conditions will assist in developing realistic pavement performance fatigue models. A field investigation programme was developed at the University of Waterloo to quantify thermal-induced strains in typical Eastern Canadian climate conditions. The main objective of this field study was to measure and compare the amplitude of load- and thermal-induced strains over a 1-year monitoring period. Results indicated that the average monthly thermal-induced strains were higher than the load-induced strains by a 49 kN wheel load moving at 25 km/h. Although the frequency of thermal-induced strains is lower than the traffic loads, damage from thermal-induced strains could be more than load-induced strains due to higher amplitudes.