## 4 Summary of Findings  
In this study, the researchers adopted bagasse and coconut peat, replacing mineral fillers to find the potential of adopting waste materials in the asphalt industry. Also, a comprehensive experiment was completed to investigate the effect of different fillers on moisture damage resistance. In addition, the POTS test was verified to be a potential method in measuring moisture damage resistance in a laboratory.  
The experimental results indicate that the TSR is dependent on aggregate type and filler content. The following points summarize the main findings of the study.  
* The results show that TSR values for 20% and 30% filler contents are above 0.7 for the limestone aggregate. This indicates that both waste natural fillers (i.e., bagasse and coconut peat) can be used as fillers at 20% and 30% by volume to prevent the moisture damage in asphalt mixture at high traffic volume.
* Using both bagasse and coconut peat fillers could give higher TSR than limestone filler for 30% filler content for granite aggregate at high traffic volume.  
Figure 9: Correlation of TSR between ITS and POTS tests.  
* Results also showed that filler contents affect the moisture damage resistance at high traffic volume. Moisture damage resistance is dependent on type of aggregate used. When limestone was used as the aggregate, the TSR values presented higher at higher filler content, whereas the TSR values presented lower at lower filler content for the granite aggregate.
* The POTS specified in ASTM C 1583 was adapted for measuring the direct tensile strength for the asphalt mixture. Results showed the POTS values were much higher (about 5-23 times) than the ITS values for the dry and wet conditions. This is logical, as the POTS uses the concept of direct tensile strength method, which can give higher values and even increase the temperature testing.
* The preliminary results are promising in terms of creating a preparation process in which samples were cured at maximum temperature of PG for 24 h in the dry condition, while samples were cured in a water bath for 2 h in. the wet condition. Thus, the POTS test can successfully measure the effect of moisture on asphalt mixtures.
* Results also showed that asphalt mixtures with bagasse and coconut peat fillers can effectively prevent the moisture damage resistance. In addition, with the preliminary result, it was found that the POTS test showed a very good R\({}^{2}\) for a relation of TSR with the ITS test. The conclusion of the relationship was not therefore proven because the findings of this analysis are preliminary. Further scenarios of asphalt mixtures should be developed to confirm whether these two methods are connected to linear or other curve fittings.
* The TSR values for the POTS test were approximately 0.65-times lower than those of the ITS test. The reason can be attributed to the different curing temperature, curing time, and concept of testing. Therefore, to establish the TSR specification of the POTS test, different scenarios of curing temperature, curing time, and asphalt mixtures should be used.
* Results showed that the TSR presented in the POTS test for the asphalt mixture, which showed the mixtures with granite filler gave lower TSR than those with limestone filler. This result is comparable to the stripping point presented in Hamburg Wheel Tracking Test (HWT), which showed the same trend as TSR in the POTS test [27].