# Enhancing Asphalt Binder Performance and Storage Stability with Trinidad Lake Asphalt (TLA)
## 3 Results and Discussion  
### Rotational Viscosity  
Viscosity is a crucial parameter for evaluating the workability of asphalt binders, especially during the transition from production to construction phases. Figure 2, with standard errors and a linear exponential equation, demonstrates that at 135 \({}^{\circ}\)C, before conditioning, a clear trend emerges: the addition of Trinidad Lake Asphalt (TLA) to the virgin asphalt binder leads to an increase in viscosity. This rise is attributed to the inherently high viscosity of TLA. Interestingly, an anomaly is observed where the binder with 20%TLA replacement shows lower viscosity values compared to the 10%TLA-modified asphalt, although these values remain higher than those of the virgin binder. Notably, all modified binders are considered workable at this temperature, as their viscosity values are well below the 3000 cP threshold.  
When the temperature is increased to 180 \({}^{\circ}\)C before conditioning, the viscosity trend remains consistent with the observations at 135 \({}^{\circ}\)C. After conditioning, both the top and bottom portions of the samples were tested at 135 \({}^{\circ}\)C and 180 \({}^{\circ}\)C. At 135 \({}^{\circ}\)C, it was found that the viscosity values at the bottom were higher compared to the original and top portions. Additionally, the top and original condition values were nearly identical. However, as the temperature increased to 180 \({}^{\circ}\)C, a significant change in the trend was observed. At this higher temperature, the top portion of the sample, the virgin binder, and the binder modified with 10%TLA showed higher viscosity values compared to the bottom portion, as illustrated with standard errors and the linear exponential equation demonstrated in Figures 3 and 4. This is because TLA has high viscosity and density, and upon heating,TLA has the tendency to settle more in the bottom portion, leading to a relatively lighter and less viscous top portion initially. However, with prolonged heating, the top portion might experience increased viscosity due to the evaporation and aging effects [6].  
Figure 3: Viscosity at 135 \({}^{\circ}\)C of the TLA modified binders after conditioning considering the top and bottom parts.  
Figure 2: Viscosity at 135 \({}^{\circ}\)C and 180 \({}^{\circ}\)C of the TLA modified binders at original condition.  
The variations in viscosity have significant implications for pavement life. Higher viscosity values generally indicate greater resistance to deformation and rutting under high temperatures, enhancing the pavement's durability and longevity. However, excessively high viscosity can lead to challenges in workability and compaction during construction, potentially resulting in inadequate pavement density and increased susceptibility to cracking. The observed differences in viscosity between the top and bottom portions of conditioned samples suggest variations in the binder's homogeneity and stability, which could affect the pavement's performance and structural integrity. Therefore, optimizing the viscosity of asphalt binders through the precise control of additives like TLA is essential for achieving a balance between workability during construction and long-term pavement performance.  
This refined understanding of viscosity behavior in asphalt binders underscores the importance of meticulous material selection and process control to ensure optimal performance and durability in road construction projects.