## 4 Results and Discussion
### Moisture-Induced Damage Properties  
The bond strength properties of the CB, CRMB, and PMB binders were evaluated using the BBS test based on the POTS and BSR values. Table 7 shows the variation in POTS\({}_{\text{dry}}\) as well as POTS\({}_{\text{wet}}\) with the considered granite aggregate type of the CB, CRMB, and PMB binders. It is clear from the result that the addition of modifiers resulted in an increase in bond strength for both dry and wet conditions. For instance, increases in the POTS\({}_{\text{wet}}\) values by 10.5% and 23.3% were observed for the CRMB and PMB binders compared to the CB binder. It is important to note that the interaction between the modifiers and asphalt binders plays an important role and may affect the overall bond strength with the aggregate, as evident from the plot. The BSR values of the CB, CRMB, and PMB binders were 0.90, 0.92, and 0.94, respectively. A higher value of BSR is desirable, as it represents a relatively lower degree of decrease in POTS\({}_{\text{wet}}\) due to damage induced by the presence of moisture. It is clear from the  
Figure 7: Correlation between wheel tracking and the Multiple Stress Creep Recovery (MSCR) test: (a) Rut depth v/s Jnr; (b) Dynamic stability v/s Jnr; (c) Rut depth v/s %R; (d) Dynamic stability v/s %R. results that the addition of modifiers resulted in an increase in the BSR values. For instance, increases in the BSR values by 2.6% and 4.7% were observed for the CRMB and PMB binders compared to the CB binder. Finally, it can be concluded that the CRMB and PMB binders had a negligible effect on the moisture-induced damage properties. This is attributable to the higher binder content, which increases the film thickness, making the mixture water-resistant [14; 15]. Moisture-induced damage properties such as the ITS and TSR values of the CB, CRMB, and PMB mixtures are presented in Table 7. The results of the ITS test clearly indicate that the CRMB and PMB mixtures showed higher ITS values compared to that of the CB mixture for both dry and wet conditions. For instance, increases in the wet ITS values by 5.1% and 15.2% were observed for the CRMB and PMB mixtures compared to the CB mixture. It is to be noted that some of the Departments of Transportation in the USA have specified a minimum ITS value (Illinois center for transportation recommends the minimum ITS value as 414 kPa). However, the wet ITS values of the CB, CRMB, and PMB mixtures fulfilled the minimum requirement criteria. In addition, the TSR values of the CB, CRMB, and PMB mixtures were 87.9%, 90.1%, and 93.5%, respectively. The results of the TSR values indicate that the CB, CRMB, and PMB mixtures fulfilled the minimum TSR (85%) requirement, as suggested in SP-02 [26]. Finally, it can be concluded that the PMB mixture had increased resistance to moisture-induced damage, while the effect of the CRMB mixture was negligible compared to that of the CB mixture. The moisture-induced damage properties were also analyzed using the correlation between the ITS and BBS test, as shown in Figure 8. It is clearly evident that higher TSR and BSR values indicated a better resistance to moisture-induced damage. The ITS and TSR values had a good correlation, with an R2 of 0.972 and 0.893 with respect to the POTS and BSR values, respectively. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Mix.**} & \multicolumn{3}{c}{**BBS**} & \multicolumn{3}{c}{**ITS**} \\  & \multicolumn{2}{c}{**POTS Dry [MPa]**} & **POTS Wet [MPa]** & **BBR** & **ITS Dry [kHz]** & **ITS Wet [kHz]** & **TSR** \\ \hline \multirow{2}{*}{**CB**} & Value & 2.34 & 2.10 & 0.90 & 781.67 & 686.67 & 87.85 \\  & SD & 0.02 & 0.02 & 0.00 & 2.89 & 5.77 & 0.64 \\  & Value & 2.50 & 2.32 & 0.93 & 805.00 & 723.33 & 89.86 \\ \multirow{2}{*}{**CRMB**} & SD & 0.02 & 0.03 & 0.02 & 5.00 & 2.89 & 0.30 \\  & Value & 2.75 & 2.58 & 0.94 & 851.67 & 796.67 & 93.54 \\ \multirow{2}{*}{**PMB**} & SD & 0.01 & 0.01 & 0.01 & 2.89 & 2.89 & 0.02 \\ \hline \hline \end{tabular} Note: SD—standard deviation.  
\end{table}