Prediction of high-temperature asphalt binder properties based on Brookfield viscometer values

Abstract

The objective of this research was to develop an empirical model which may be used to predict the performance grade (PG) of asphalt binders given only the viscosity of the binder at 135°C. Data from two existing studies (5 binder sources and 10 crumb rubber variations) were utilised in the development of the model. The empirical models were evaluated using data obtained from a fractional factorial experimental design using five previously untested base binders; 19 crumb rubber modified binders were subsequently evaluated. The developed models for G*/sin δ, PG high failure temperature, crumb rubber concentration yielded good correlations with respective R-squared values of 0.89, 0.81 and 0.76 in the verification study. These findings confirm that it is possible to empirically model the high-temperature behaviour of modified asphalt binders using only the binder viscosity at 135°C as a reference point.

Keywords:

• non-linear model
• viscosity
• rutting susceptibility
• failure temperature
• crumb rubber
• rubberised asphalt

Acknowledgements

This study was supported by the ARTS in the Civil Engineering Department at Clemson University, Clemson, South Carolina, USA. The authors wish to acknowledge and thank South Carolina's Department of Health and Environmental Control (DHEC) for their financial support of this project.