## 3 Materials, Sample Preparation, and Experimental Methods
### Experimental Methods  
The experimental design included the evaluation of the asphalt binder and mixture properties, as summarized in Table 4. Asphalt binder properties such as MSCR and BBS and the viscosity test of the CB, CRMB, and PMB binders were evaluated. A rotational viscosity test was carried out to characterize the workability of the asphalt binders as per ASTM D4402 using a Brookfield viscometer. The viscosity values of unaged CB, CRMB, and PMB binders were measured in the temperature range from 120 to 180 \({}^{\circ}\)C at intervals of 15 \({}^{\circ}\)C.  
The MSCR test was conducted on short-term aged CB, CRMB, and PMB binders using DSR with a parallel plates (oscillating plate and fixed plate) arrangement at 64 \({}^{\circ}\)C as per American Association of State Highway and Transportation Officials (AASHTO) TP70, as shown in Figure 2.  
The samples were subjected to 10 loading cycles; each consists of 1 s as a creep period and 9 s as a recovery period at standard stress levels of 0.1 and 3.2 kPa. The strain response was recorded over the entire loading and recovery periods. Based on the recorded strain response, the recovery (%R) and non-recoverable creep compliance (Jnr) values were calculated as per Equation (1) and Equation (2), respectively. Further, the Jnr measured at 3.2 kPa was utilized to check the suitability of different asphalt binder combinations for different traffic levels, as per AASHTO MP 19. Moreover, the difference in the Jnr value (Jnr_diff) corresponding to the stress levels of 0.1 and 3.2 kPa was also analyzed to investigate the influence of modifiers on the stress sensitivity aspect (Equation (3)). \[\text{R (\%)}=\ \frac{\sum_{n=1}^{10}\bigl{(}\frac{\varepsilon_{1}-\varepsilon_{10} }{\varepsilon_{1}}\bigr{)}_{n}}{10}\times 100\, \tag{1}\]  
\[\text{J}_{\text{nr}}=\ \frac{\sum_{n=1}^{10}\bigl{(}\frac{\varepsilon_{10}}{ \tau}\bigr{)}_{n}}{10}\, \tag{2}\]  
\[\text{J}_{\text{nr\_diff}}(\%)=\ \frac{\text{J}_{\text{nr\_3,2,-J}_{\text{nr\_0, 0.1}}}}{\text{J}_{\text{nr\_0,0.1}}}\times 100, \tag{3}\] \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{1}{c}{**Response Property**} & \multicolumn{1}{c}{**Source of Variance**} \\ \multicolumn{1}{c}{} & **Mixture Type** & **Binder Content** & **Number of Specimens** \\ \hline \multirow{3}{*}{Workability} & Mix design properties & 3 & 3 & \(3\times 9=27\) \\  & Viscosity & 3 & 1 & \(3\times 3=9\) \\  & Baking method & 3 & 1 & \(3\times 3=9\) \\  & Looking point method & 3 & 1 & \(3\times 3=9\) \\ \hline \multirow{2}{*}{Rutting} & Multiple Stress Creep Recovery Test & 3 & 1 & \(3\times 3=9\) \\  & Wheel tracking device & 3 & 1 & \(3\times 3=9\) \\ \hline \multirow{2}{*}{Moisture-induced damage} & Modified Lottman test & 3 & 1 & \(3\times 3=9\) \\  & Bitumen Bond Strength & 3 & 1 & \(3\times 3=9\) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Experimental design of the various performance parameters. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Property** & **CB** & **CRMB** & **PMB** & **Standard** \\ \hline Penetration at 25 \({}^{\circ}\)C, 0.1 (mm) & 65 & 35 & 42 & ASTM D5 \\ Softening point (R\&B) (\({}^{\circ}\)C) & 55 & 60 & 70 & ASTM D36 \\ Ductility at 25 \({}^{\circ}\)C (cm) & 110 & 35 & 85 & ASTM D113 \\ Flash point (\({}^{\circ}\)C) & 300 & 230 & 260 & ASTM D92 \\ Retained penetration, after short term aging (\%) & 54 & 32 & 28 & ASTM D5 \\ Ductility test at 25 \({}^{\circ}\)C, after short term aging (cm) & 67 & 20 & 60 & ASTM D113 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Properties of the asphalt binders. where R (%) = percentage recovery, \(\varepsilon\)10 = strain at the end of each recovery period, \(\varepsilon\)1 = strain at the end of each creep loading period, Jnr = non-recoverable creep compliance (kPa-1), and \(\tau\) = standard stress level during the creep loading phase. Jnr_0.1 and Jnr_3.2 are the non-recoverable creep compliance values for the creep loadings of 0.1 and 3.2 kPa respectively.