## 3 Result and Discussion
### Modified Asphalt Performance at High Temperature before and after RTFOT  
#### 3.5.1 Putting Factor (G*/Sin8)  
The value (G*/Sin8) is the quotient of the modulus complex (G*) and phase angle (\(\delta\)), which can describe the performance of asphalt against rutting at high temperatures. Increasing the modulus  
Figure 8: (**A**) Cavities that are not filled with modified asphalt. (**B**) Filler which fills the voids between the aggregates. complex (G*) and decreasing the phase angle (\(\delta\)) is desirable to produce asphalt with high rutting resistance. The higher the value (G*/Sin\(\delta\)) shows the performance of asphalt in resisting rutting (anti-rutting) at high temperatures is better [35]. Figure 9 shows the values (G*/Sin\(\delta\)) before and after RTFOT of asphalt pen grade 60/70, asphalt with 10% crepe rubber (B2 non-TMQ), and B2. Figure 9 shows an increase (G*/Sin\(\delta\)) after adding 10% crepe rubber and 2% TMQ (Sample B2 non-TMQ and B2). However, it decreases with increasing test temperature because the asphalt is viscous. The increase in value (G*/Sin\(\delta\)) in the B2 non-TMQ and B2 samples indicates that the asphalt properties are getting harder after the addition of crepe rubber. The highest value (G*/Sin\(\delta\)) reached 6.91 kPa before RTFOT, while asphalt pen grade 60/70 was only 2.86 kPa, and B2 non-TMQ was only 5.46 kPa. This is closely related to the decreased penetration value of asphalt after the addition of 10% crepe rubber and 2% TMQ compared to asphalt pen grade 60/70. This is due to the increase in cohesion and adhesion and the bitumen's resistance to low temperatures, marked by an increase in the softening point value (see Figure 2). In this case, crepe rubber plays a role in increasing the cohesion and adhesion of the asphalt. One of the factors affecting bitumen's resistance to rutting and fatigue is the modified asphalt's cohesion and adhesion properties. The addition of crepe rubber increases the asphalt mixture with aggregates to increase asphalt cohesion and adhesion performance. However, the addition of TMQ (sample B2) shows that the rutting factor decreases before the TFOT process is carried out (see Figure 9). This is because the penetration of asphalt increases as the concentration of TMQ in the mixture increases. The increase in penetration indicates that the asphalt's cohesion and adhesion properties decreased due to the antioxidant TMQ, which melts during mixing. TMQ antioxidant has physical properties such as wax, causing the asphalt's viscosity to decrease, and the fraction of maltene in the asphalt increases after mixing. The value of the rutting factor (G*/Sin\(\delta\)) of the 60/70 pen grade asphalt, B2 non-TMQ, and B2 asphalt samples increased with aging during RTFOT and decreased with increasing temperature. The value (G*/Sin\(\delta\)) after RTFOT has a good appearance with a decrease in the value of asphalt penetration after RFTOT. This indicates that it is getting louder after RTFOT. The value (G*/Sin\(\delta\)) increases drastically in sample B2 due to the higher elastic proportion after RTFOT. The increase in the rutting factor in sample B2 after RTFOT showed that the cohesion and adhesion of asphalt increased rapidly due to TMQ's performance stabilizing the rubber phase on the asphalt and preventing aging. This result correlates with the increase in Marshall stability, where asphalt with the addition of crepe rubber and 2% TMQ (sample B2) has a high stability value (see Figure 5). High stability indicates that the sample has high rutting and fatigue resistance. However, a significant increase in value (G*/Sin\(\delta\)) is not expected as this indicates the bitumen is too stiff and decreases the elastic properties of the asphalt. Asphalt with good rutting resistance must be rigid enough and elastic enough to return to its original shape after loading [36]. The DSR test results of the asphalt B2 non TMQ and B2 samples showed that the asphalt performance after rubber was better than that of asphalt pen grade 60/70.