Performance of Multiaxial Paving Interlayer–Reinforced Asphalt Pavement

Abstract

Paving interlayers have been used in asphalt concrete (AC) overlays for a variety of benefits. An earlier study showed that different paving interlayers improved mixture performance, while the multiaxial interlayer provided the best overall laboratory performance. This paper presents further investigation of the reinforcing effect of the multiaxial interlayer on the entire pavement. Pavement structural analysis using finite-element method (FEM) analysis and several specialized commercially available software were conducted, and field test sections were established and surveyed to further validate findings from the previous study. The pavement structural analyses were in agreement that using interlayer could improve fatigue crack resistance and extend service life. The three-yarn biaxial interlayer showed the best reinforcement potential of fatigue crack resistance, followed by the multiaxial interlayer and the two-yarn biaxial interlayer. The FEM analysis indicated that the multiaxial interlayer could improve stress distribution more effectively than the two-yarn biaxial interlayer. Preliminary results from field evaluations of test sections showed that pavement performance was improved if reinforced by interlayers, in terms of reduced amount and severity of cracking. Further monitoring of field test sections are recommended to give clearer projection of the utility of the paving interlayers in cold regions.