Asphalt binders characterization and modeling x-ray diffraction

Abstract

Cracking is a common occurrence in asphalt pavements in colder climates, while pavements in hotter climates experience rutting; both of which are considered on-going problems from an industry standpoint. Asphalt presents in crude oil was studied to know their structure with the help of X-ray diffraction (XRD). Six samples of Asphalt binder were taken from Canada and USA then converted into thin films of 1mm to get XRD pattern. In addition, Cu-K-a monochromatic radiations were used at 40kV using a Rigaku DMax 2200V-PC at 40 mA with scan ranges from 2θ= 5⁰ to 35⁰ and 60⁰ to 110⁰. Mathematical functions such as Pearson VII and Pseudo-Voigt are used to profile fit the data obtained by the XRD. After profile fitting, they are modeled using GFF i.e. Generalized Fermi Function in Mathematicaᵀᴹ. The analysis showed a correlation among the three mathematical functions. The outcomes discussed here substitute to the accuracy of profile fitting whereas the exponents of Pearson VII and pseudo- Voigt Lorentzian differ. The Lorentzian values of Pseudo- Voigt are 0.3, 0.5, and 0.7 whereas the Exponent values of Pearson VII are 0.5, 1.0, and 1.5, and 3 backgrounds (linear, 3ᴿᴰ order polynomial, and parabolic) were applied in profile fitting. Further, profile fittings’ accuracy made crystallite parameters to produce approximate results when calculated.