## 3 Results
### Dynamic creep Curve and Ultimate Strain  
Figure 12 illustrates the relationship between the accumulated strain and the number of cycles for the CBA mixtures. The results demonstrated a positive correlation between the number of load cycles and the increase in the accumulated permanent strain for all CBA mixtures. The findings indicated that all CBA mixtures reached the secondary phase of the creep curve. The first phase is determined by the recoverable elastic strain resulting from the densification of the mixture, whereas the subsequent phase is associated with the viscoelastic strain arising from cumulative axial strain [67; 68]. The CBA mixture did not advance to the tertiary stage in this test, as the sample was terminated either after 1800 load cycles or upon reaching a total strain of 100,000 \(\upmu\)s.  
Figure 13 presents the results of the ultimate strains for all CBA mixtures. The results indicated that the CBA-0 mixture showed the greatest strain value compared to other mixtures with increased CBA contents. The ultimate strain for the CBA-0 mixture was measured at 32,906 \(\upmu\)s. The mixtures with higher cumulative axial strain values demonstrated a reduced capacity to resist rutting [69]. The ultimate strain demonstrated a negative correlation with the increase in CBA content, up to 50% of CBA replacement, as presented in Figure 9. The ultimate strain of the CBA-10 mixture was measured at 21,535 \(\upmu\)s, representing 0.65 times the ultimate strain of the control mixture, as tabulated in Table 9. Subsequently, the CBA-20 and CBA-30 mixtures demonstrated a gradual decrease in their ultimate strain values, with normalised values of 0.63 and 0.62 times, respectively, compared to the control mixture.  
Figure 12: Dynamics creep curve for CBA mixtures.  
\begin{table}
\begin{tabular}{c c c} \hline
**Mixture** & **CBA** & **Normalized** \\ \hline CBA-0 & 8351 & 1.00 \\ CBA-10 & 8262 & 0.99 \\ CBA-20 & 7803 & 0.93 \\ CBA-30 & 7458 & 0.89 \\ CBA-50 & 7219 & 0.86 \\ CBA-70 & 7019 & 0.84 \\ CBA-100 & 6959 & 0.83 \\ \hline \end{tabular}
\end{table}
Table 8: Normalized resilient modulus of CBA mixtures.  
Table 9 indicates that the CBA-50 mixture demonstrated enhanced resistance to permanent deformation compared to the other CBA mixtures. The ultimate strains recorded at the lowest value for the CBA-50 mixture were measured at 13,747 us. The measured value was determined to be 0.42 times that of the control mixture. This finding suggests that increasing the proportion of CBA offers the potential to enhance the mixture's ability to withstand permanent deformation. The reduction in the ultimate strain value is due to enhanced interlocking between the aggregate and CBA particles, which is facilitated by the rough and irregular shape of the CBA. Increased interparticle friction contributes to the stabilization of the mixture, thereby minimizing the strain accumulation during sustained loading. This mixture exhibited reduced ultimate strain, indicating enhanced resistance to permanent deformation in the creep test. The observed patterns of decline began to shift at CBA-70. The ultimate strains recorded for CBA-70 and CBA-100 were 26,170 us and 32,070 us, respectively. Even though there were increases in the ultimate strain value for CBA-70 and CBA-100, it is essential to note that the values were still lower than that observed in the CBA-0 mixture.