Characterizing the effects of geosynthetics in asphalt pavements

Abstract

Retarding reflective cracking in asphalt overlays is a serious and inevitable challenge to asphalt pavement engineers. Anti-reflective cracking systems using geosynthetic interlayers are believed to be a solution able to improve the pavement performance. The paper evaluates the effects of the inclusion of different types of geosynthetic and is focusing on the results of monotonic and dynamic tests. Shear tests and indirect tensile strength tests were carried out as interface characterization tools, showing the ability of the geosynthetics to prevent separation. Non-conventional fatigue tests were performed on reinforced, and unreinforced, notched beams to obtain a better understanding of the behaviour of the geosynthethics in retarding crack propagation. The main parameters, such as the applied load, the crack opening and the vertical displacements were monitored. The void structure of the beams was visualized using X-ray tomography, giving useful information about the interlayer effects on compaction. Furthermore a finite element model, based on the experimental results, was developed to predict reinforced specimens behaviour. The findings showed the benefits of using the geosynthetics in asphalt overlays, to prevent crack propagation. © RILEM 2012.