Experimental Evaluation of the Interaction between Geosynthetic Reinforcements and Hot Mix Asphalt

摘要

The advent of interlayer reinforcements with a wide range of stiffness properties has provided the opportunity to produce a specially-designed composite material that can enhance pavement performance in various aspects (e.g., rutting, fatigue cracking, reflective cracking). However, reinforcements may negatively affect the bonding between asphalt layers. The objective of this paper is to evaluate experimentally the interlayer de-bonding effect. In particular, reinforced and unreinforced asphalt specimens were tested in a direct shear test setup and their interlayer bond strength was characterized. The reinforcement inclusions used in the testing program involved synthetic materials made from various polymers, including polyester, polyvinyl alcohol, and glass fiber. Results of the experimental program indicated that the de-bonding effect impacts not only the maximum bond strength, but also the stiffness and the average interlayer shear strain at the maximum bond strength. Moreover, coverage ratio and the thickness of the reinforcement yarns were identified as additional important parameters in characterization of the interlayer de-bonding effect.