Buton Rock Asphalt (BRA) refers to the natural rock asphalt natively produced on the Buton island of Indonesia. It is often used as a modifier to enhance the performance of asphaltpavement. However, the segregation of BRA in BRA-Modified Asphalt (BRA-MA) has restricted its application. This study aims to investigate how the particle size and content of BRA affect the physical properties and storage stability of BRA-MA. Penetration, softening point, viscosity, and viscosity-temperature susceptibility (VTS) were analyzed. The evaluation method of storage stability was discussed and determined. The segregation of BRA in BRA-MA of static storage and transportation process were simulated and tested. The results suggest that the softening point and viscosity were positively correlated to BRA content and inversely determined by particle size. Penetration, VTS, and ductility were reduced due to the decline in particle size and increment of BRA content. The index of segregation value based on viscosity difference showed better statistical and quantitative significances than the softening-point difference in evaluating the storage stability. The particle size and content of BRA are positively correlated to the segregation of BRA-MA. Both the storage temperature and time were positively correlated to the segregation of BRA-MA. We prove that the relationship between specific surface area and segregation are power functional. BRA-MA with BRA whose 50% particle sizes are lower than 13.6 μm showed low segregation in transportation.

Buton rock asphalt (BRA) has been used in asphalt pavement for its contribution to high-temperature stability. However, how BRA affects the durability of a corresponding asphalt mixture requires systemic discussion. This study investigated how BRA affected durability in terms of the fatigue resistance, thermo-oxidative aging resistance, and long-term moisture stability of asphalt mixture. Furthermore, improvement of the long-term moisture stability of asphalt mixture containing BRA modified asphalt (BRAM) was also included. An AC-20C asphalt mixture based on BRA asphalt, neat asphalt, and SBS-modified asphalt were prepared and their high-temperature, low-temperature, and moisture performance were examined. A semi-circular bending cyclic loading test was used to characterize fatigue performance. Thermo-oxidative aging tests in both the short-term and long-term were used to indicate the aging performance. Freeze–thaw cyclic splitting tests were carried out to investigate BRAM’s long-term moisture stability. Finally, the optimization and enhancement of BRAM’s long-term moisture stability was discussed in terms of ceramic, basalt, and polyester fiber, as well as hydrated lime. Results showed that BRA can enhance the high-temperature, low-temperature, and moisture performance of BRAM. The cracking fatigue resistance and thermo-oxidative aging resistance of BRAM were also improved by BRA. The long-term moisture stability of BRAM was lower than that of the asphalt mixture based on SBS and neat asphalt. It was found that the long-term moisture durability of BRAM can be optimally enhanced by replacing mineral filler with 50% hydrated lime by equal volume and using 0.2wt% ceramic fiber as an additive in BRAM.