Prediction of Linear Viscoelastic Rheological Properties for Composite Nanosilica/Polyethylene Modified Bitumen Using Response Surface Methodology

This study evaluates the suitability of response surface methodology (RSM) to describe the linear viscoelastic (LVE) rheological properties of composite nanosilica/polyethylene modified binder. Two independent and three response variables were investigated, the independent variables were temperature and nanosilica content whilethe response variables are phase angle and complex modulus. Each of the independent variables was varied over three levels. The temperature was varied in the range of 35 to 55 OC and nanosilica was varied from 2 to 6%. RSM was used for the evaluation based on Central Composite Design (CCD) design. From the results, a high correlation coefficient (R2) of 0.9999 and 0.9953 were obtained for complex modulus and phase angle. This confirms that the experimental values obtained are in real agreement with the developed quadratic models. Analysis of the individual effects of temperature and nanosilica content reveals that all the responses are influenced by the interaction of both the two independent variables but highly influenced by temperature than nanosilica content