Comparative Assessment of Visco-Elastic and Visco-Plastic Behavior of Asphalt Concrete under Environmental Influence

The visco-elastic and visco-plastic behavior of asphalt concrete mixture are highly susceptible to the variation in the pavement temperature. In the present assessment, asphalt concrete slab samples were prepared with optimum binder requirement using laboratory roller compaction. Beam specimens were obtained from the slab samples and tested under dynamic flexural stresses for fatigue life using constant strain level of 750 microstrain. Three testing temperatures have been implemented (5, 20, and 30) ℃. The variation in the visco-elastic and visco-plastic behavior in terms of permanent deformation, phase angle, cumulative dissipated energy, and flexural stiffness to the testing temperatures were assessed. It was concluded that the visco-elastic and visco-plastic behavior of asphalt concrete are highly sensitive to the variation in testing temperature. It was observed that at the visco-plastic stage of failure, the energy dissipation increases by (2, 1.5, 29) folds for the testing environments of (5, 20, and 30) °C respectively as compared with the cumulative dissipated energy at the visco-elastic stage of failure. The phase angle declined to (55, 20, and 30) ° for (5, 20, and 30) °C testing environment respectively at the visco-plastic stage of failure as compared with that at visco-elastic stage of failure. The flexural stiffness at the visco-plastic stage of failure declined by (60, 80, and 92) % at (5, 20, and 30) °C testing temperature respectively as compared with the flexural stiffness at the visco-elastic stage of failure.