Statistical Methods on Low Temperature Performances of RAP Mortars Without Extracted Binders

Abstract

Due to its aged binder, RAP generally has a negative effect on the low temperature properties. Therefore, it is necessary to explore the characteristics of RAP at a low performance temperature. However, there are few studies on the low temperature performances of RAP mortars by the data processing method. This study aims at understanding the influence of several variables on low temperature properties of RAP mortars without extracted binders, from a statistical point of view. The independent variables include three base binders, three RAP contents, three test temperatures and six RAP sources. In addition, this study employed analysis of variance (ANOVA) and partial correlation analysis to analyze the stiffness and m-value. Statistical results showed that the changes in base binders type, test temperature and RAP content had statistically significant influences on low temperature performances. In addition, the test temperature played the most important role, followed by RAP content and base binder type. However, the RAP source had slight effects on stiffness and m-value. Moreover, stiffness and m-value were highly correlated with a Pearson correlation coefficient of 0.795. In summary, statistical analysis method used in this study was simple and effective to analyze the low-temperature performance and was able to identify the impacts of various variables on the low temperature characteristics.