Fracture Behavior of Geosynthetic Interlayers in Road Pavements

Abstract

For different overlay systems currently used in practice (PGM 14, PGM-G, and TENSAR grid) the fracture behavior of the interface between interlayer and asphalt overlay as well as of the entire system is characterized and analyzed. A simple and easy-to-use wedge splitting test according to Tschegg is carried out in order to evaluate both the interface and reflective cracking behavior. The specimens used in this test consist of modified cores taken from road pavements. This investigation demonstrates that the overlay systems show considerable variation in their fracture mechanism parameters (such as resistance to crack propagation of the interface or propagation of reflection cracks), but only minor differences with regard to the other properties (such as bonding tensile strength of the interlayer compound system or the notch tensile strength of the reflective crack). The effectiveness of the interlayer system is diminished when the resistance against crack propagation in the interface is reduced.