Implementation of Image Processing Technique to Assess the Surface Free Energy of Asphalt Binder

Abstract

The adhesive properties of asphalt binder are considered as a major issue in the durability of the pavement. When asphalt cement does not match the standard specification required for paving work, one of the existing remedy processes is to implement modifiers to enhance the quality. Image processing technique can detect the variation in the adhesive properties through the assessment of surface free energy of the binder. In the present assessment, asphalt cement binder has been treated with varying percentages of two types of modifiers, Carbon Black (5, 10, and 15) %, and Sulfur (3, 5, 7, and 10) % by weight of asphalt cement binder. The image processing technique has been implemented for evaluating the surface free energy components (dynamic and static angles of contact) of the modified asphalt cement using the traditional Sessile drop and Wilhelmy plate methods. The aim of the present investigation is to assess how the implementation of image processing technique can alter the surface free energy components of asphalt binder after the addition of the modifiers. However, the surface free energy components of the control binder are also determined for comparison. Based on the testing results, it was concluded that Carbon black modifier is considered more appropriate additive for the binder since it exhibits an ultimate total surface free energy increment of 7.7% and 6% as compared with 2.8% and 3.1 % for sulfur when Wilhelmy plate and Sessile drop methods are implemented respectively as compared with those of the control asphalt binder.