Thermo-plastic fiber’s reinforcing effect on hot-mix asphalt concrete mixture

•Average interfacial bond strength resulted in the value of τ = 0.12 N/mm2.•Fiber’s contribution to resisting the failure is approximately 25.5%.•The maximum tensile stress at the peak of 0.47 N/mm2.

We propose a method for predicting the direct tensile bond strength of plastic fiber-reinforced hot-mix asphalt (HMA) mixtures. The toughening effects of the plastic fiber-reinforced HMA mixtures are characterized using the direct tensile loading test. A method for calculating the effective fiber volume fraction along the failure plane is proposed to estimate the interfacial bond strength along the failure plane. The average interfacial bond strength resulted in the value of τ = 0.12 N/mm2. Comparing to the maximum tensile stress at the peak of 0.47 N/mm2, the fiber’s contribution to resisting the failure is approximately 25.5%. The generality of the direct tensile loading approach was confirmed by the experimental data from the direct tensile tests and three-point bending beam tests.