Respons Campuran Asbuton–Gondorukem terhadap Variasi Suhu Pencampuran: Stabilitas Marshall dan Kekuatan Sisa setelah Perendaman

The use of Asbuton as a local asphaltic material combined with bio-based additives requires appropriate processing conditions to obtain consistent mixture performance. This study aims to evaluate the response of Asbuton–gondorukem asphalt mixtures to different mixing temperatures based on Marshall stability and retained strength after immersion. The mixtures were prepared at mixing temperatures of 60°C, 90°C, and 120°C, with immersion durations of 0, 1, 2, and 3 days. A total of 36 specimens were prepared, consisting of three specimens for each combination of mixing temperature and immersion duration. Marshall stability was analyzed descriptively by comparing the average stability values and the Retained Strength Index (IKS), calculated as the ratio of stability after 3 days of immersion to the initial stability. The results showed that the highest initial stability was obtained at 120°C, reaching 4,204.25 N, whereas after 3 days of immersion the highest stability was obtained at 90°C, reaching 4,034.57 N. The IKS values were 126.32%, 130.53%, and 84.11% for mixing temperatures of 60°C, 90°C, and 120°C, respectively. The results indicate that the mixing temperature associated with the highest initial stability did not necessarily produce the highest stability after conditioning. The 90°C condition was therefore identified as the most prospective condition for further investigation within the temperature range studied, rather than being established as the optimum mixing temperature. Further research is required using additional performance parameters, including volumetric properties, flow, Marshall Quotient, moisture susceptibility, and durability.