Selection of Optimum Nano-Modifier Content to Ensure Proper Performance of the Asphalt Binder

Abstract

There is a growing need to improve the performance properties of asphalt binders in order to minimize the occurrence of failure mechanisms such as permanent deformation, fatigue, adhesiveness and moisture damage. Nanostructured materials have taken a scientific-industrial boom as asphalt modifiers due to their mechanical, thermal and electrical properties, among others. The chemistry of the nano-material, and thus their inherent physical properties, ends up in each one having specific effects on the asphalt and variable blending forms depending on their nature. This paper evaluates the effect of the incorporation of nano-silica into a PG64-22 binder at various contents from 0.5% to 6.0%. Morphological, rheological and thermal analysis techniques were used to quantify the effect of asphalt binder modification. Such techniques were Differential Scanning Calorimetry (DSC), thermogravimetric (TGA) analysis, as well as Fourier transform infrared spectroscopy (FTIR) and Atomic Force Microscopy (AFM). Selection of the optimum modifier content was mainly based on DSR asphalt fatigue and rutting tests and work of adhesion analysis.