Effect of polymer modification on the ageing properties of asphalt binders: Chemical and morphological investigation

Asphalt binder is a complex material to study. Asphalt binder modification and ageing further increase this complexity. These two phenomenon affect the behaviour and performance of the binder significantly. In order to successfully characterise and understand the behaviour of asphalt binder, it is necessary to study the effect of ageing and modification at microscopic level. Over the years many researchers have used different method to study the chemical and morphological behaviour of the asphalt binder. In the present study three major morphological and chemical experimental procedures Fluorescence microscopy, Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) are used to examine the effect of polymer modification and ageing on asphalt binder simultaneously. In the study base binder is modified using styrene butadiene styrene (SBS) and ethylene vinyl acetate (EVA). Fluorescence microscopy and separation testes were used to find out the optimum binder content for both the polymer modifiers. Short term and long term ageing were simulated on the base binder as well as PMBs by using rolling thin film oven test (RTFOT) and pressure ageing vessel (PAV) test respectively. SEM and FTIR tests were conducted before and after the ageing and modification. Test results were analysed. Based on the analysis of test results, comparisons are made and conclusions are given. (C) 2019 Elsevier Ltd. All rights reserved.