<![CDATA[ABSTRAKLapis aus merupakan lapisan perkerasan jalan yang rentan mengalami kerusakan seperti retak (cracking) dan deformasi permanen, sehingga diperlukan inovasi pada campuran material. Penelitian ini bertujuan menentukan kadar aspal optimum (KAO) menggunakan aspal penetrasi 60/70 dengan penambahan crumb rubber (2,5%, 3%, 3,5%) sebagai aditif serta abu tempurung kelapa sebagai filler. Pengujian Marshall digunakan untuk mengevaluasi karakteristik campuran. Hasil penelitian menunjukkan penambahan crumb rubber dan filler berpengaruh signifikan terhadap sifat campuran. Pada kadar 3,5% crumb rubber diperoleh kepadatan 2,514 t/m³ dan VFA 78,038%, sedangkan stabilitas tertinggi 1.572,082 kg dan flow 4,490 mm terjadi pada kadar 3%. Nilai kepadatan dan VFA tinggi menunjukkan rongga udara kecil yang berpotensi menimbulkan bleeding dan rutting. Sebaliknya, kombinasi crumb rubber dan abu tempurung kelapa menurunkan kepadatan serta stabilitas, tetapi meningkatkan VIM 4,998% dan VMA 18,051%, sehingga campuran lebih fleksibel namun berisiko stripping.Kata kunci: crumb rubber, abu tempurung kelapa, ac-wc, marshall test, aditif ABSTRACTThe surface layer is a layer of road pavement that is prone to damage such as cracking and permanent deformation, necessitating innovation in material mixtures. This study aims to determine the optimum asphalt content (OAC) using 60/70 penetration asphalt with the addition of crumb rubber (2.5%, 3%, 3.5%) as an additive and coconut shell ash as a filler. Marshall testing was used to evaluate the characteristics of the mixture. The results show that the addition of crumb rubber and filler significantly affects the properties of the mixture. At a crumb rubber content of 3.5%, a density of 2.514 t/m³ and VFA of 78.038% were obtained, while the highest stability of 1,572.082 kg and flow of 4.490 mm occurred at a content of 3%. The high density and VFA values indicate small air voids that could potentially lead to bleeding and rutting. Conversely, the combination of crumb rubber and coconut shell ash reduces density and stability but increases VIM to 4.998% and VMA 18,051%, making the mixture more flexible but at risk of stripping.Keywords: crumb, rubber, coconut shell ash, ac-wc, marshall test, aditif ]]>
