## 2 Materials and Methods
### Materials Characterization  
The material used to produce the CRAM consisted of milled asphalt from the BR-381 highway. The stone dust was supplied and characterized by Arteris. The CP-II-F-32 cement and RL-1C asphalt emulsion were supplied and characterized by Stratura Asfalots. Additive like 1% to 2% cement helps form a homogeneous mix [50]. The cement content below 1% is ineffective in early strength gain, and excess cement beyond 2.5% results in brittle nature in the mixes [40; 50]. Hence, 1% of Ordinary Portland cement (OPC) was adopted to prepare the samples. In general, a value of 2 or 3% of asphalt emulsion has provided the best results for the different materials and gradations evaluated [2; 39; 51]. Hence, 3% the emulsion was adopted to prepare the samples. The particle size composition of the CRAM was determined according to the standards of the Asphalt Academy [52] and the Southern African Bitumen Association (SABITA) [53], which provide guidelines on the particle size ranges for bitumen-stabilized bases. Figure 1 shows the visual aspect of the studied mixture. The CRAM composition used the following percentages: 76% RAP, 23% stone dust, 1% cement and 3% emulsion. Figure 2 presents the granulometric curve of the mixture, the individual curves of the materials, and the granulometric limits established by the Asphalt Academy [52] and  
Figure 1: The visual aspect of the studied mixture. Sabita [53]. Stone dust was used in the composition to adjust the mixture's gradation. Table 1 shows the results of the characterization tests and the methodologies applied. The analysis of Figure 2 highlights the importance of including stone dust and cement in adjusting the gradation of the mix, addressing the deficiency of fines in the RAP. Additionally, Table 2 presents the characterization results of the asphalt emulsion used in the study. As detailed in Table 2, the RL-1C type emulsion meets the specified normative limits. The CRAM compaction was performed in a tripartite cylindrical mold with a diameter of 100 mm and a height of 200 mm. Ten layers of 2 cm each were compacted, with 21 blows each, using modified compaction energy according to the DNIT [64] brazilian standard [64] to define the optimal water content to be added to the mixture. Table 3 presents the results of density and optimal moisture content. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Test** & **Brazilian Standard** & **Result** & **Unit** \\ \hline Methylene Blue & NBR 10235 [54] & 1.5 & mg/g \\ Sand Equivalent & NBR 12052 [55] & 57.3 & \% \\ Water Absorption & NBR NM 30 [56] & 0.1 & \% \\ Real Dry Specific Gravity & NBR NM 52 [57] & 2.683 & cm\({}^{3}\) \\ Apparent Specific Gravity & NBR NM 52 [57] & 2.679 & cm\({}^{3}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Characterization of the stone powder used in the mixture. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Test** & **Brazilian Standard** & **Unit** & **Specified** & **Result** \\ \hline Saybolt Furol Viscosity, 25 °C & NBR 14491 [58] & Seconds & Max. 70 & 21 \\ Sedimentation, 5 days & NBR 6570 [59] & \% mass & Max. 5.0 & 0.4 \\ Sieve, 0.84 mm & NBR 14393 [60] & \% mass & Max. 0.1 & 0 \\ Particle Charge & NBR 6567 [61] & - & Positive & Positive \\ Dry Residue & NBR 14376 [62] & \% mass & Min. 60 & 61 \\ pH & NBR 6299 [63] & - & Max. 6.5 & 3.32 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Characterization of the emulsion. Figure 2: Granulometric curve of the mixture, the individual curves of the materials, and the granulometric limits established by the Asphalt Academy [52] and [PERSON] [53]. According to the literature, the density values of CRAMs typically range between 1.8 g/cm\({}^{3}\) and 2.25 g/cm\({}^{3}\)[2, 39, 46]. This variation depends on the emulsion content, RAP content, amount of natural aggregate, and type of compaction. In this study, the density of CRAM was 1.95 g/cm\({}^{3}\), a value similar to the findings of [PERSON] et al. [46] (1.8 g/cm\({}^{3}\) to 1.9 g/cm\({}^{3}\) in CRAMs containing 75% RAP).