Modeling the Impact of Testing Mode on the Viscoelastic Behavior of Asphalt Concrete

The variations in the viscoelastic behavior of asphalt concrete due to testing mode is assessed and modeled in the present investigation. Asphalt concrete mixture was prepared at its optimum binder requirement and compacted in slab mold with the aid of roller compaction. Beam specimens of 62 mm width, 400 mm length, and 56 mm depth were extracted from the slab samples and tested using controlled stress and strain techniques under dynamic flexural stresses. The viscoelastic properties such as the cumulative dissipated energy, phase angle, flexural stiffness, micro strain, and permanent deformation were monitored and modeled among the two testing techniques. It was observed that higher permanent deformation and micro strain are detected when the test was conducted under constant strain mode. However, higher phase angle, flexural stiffness, and energy dissipation could be observed under constant stress mode of test.