Electronic Theses and Dissertation

Pemanfaatan limbah abu sabut kelapa (ask) dan limbah plastik polyethylene terephthalate (pet) dalam campuran aspal beton lapis aus (ac-wc) menjadi salah satu alternatif untuk meningkatkan kinerja perkerasan sekaligus mendukung penggunaan material ramah lingkungan. penelitian ini bertujuan untuk menganalisis pengaruh penambahan pet dan ask terhadap karakteristik marshall dan durabilitas campuran, serta menentukan komposisi terbaik yang memenuhi spesifikasi umum bina marga 2018 revisi 2 (2020). tahap awal penelitian adalah menentukan kadar aspal optimum (kao) yang diperoleh dalam rentang 5,03%, 5,37%, dan 5,71%. seluruh nilai kao tersebut digunakan dalam pengujian dengan variasi kadar pet sebesar 5%, 7%, dan 9%. hasil pengujian marshall menunjukkan bahwa kadar pet sekitar 5% memberikan hasil terbaik dengan nilai stabilitas 1174–1185 kg, flow 2,41–2,55 mm, serta marshall quotient (mq) yang relatif tinggi. peningkatan kadar pet di atas 5% menyebabkan flow meningkat dan mq menurun, yang menunjukkan campuran menjadi lebih plastis dan kurang kaku. selanjutnya, dilakukan penambahan ask sebagai filler dengan variasi 25%, 50%, 75%, dan 100% menggunakan kombinasi kao dan kadar pet terbaik. hasil menunjukkan bahwa komposisi optimum diperoleh pada kadar ask 25% dengan nilai stabilitas 1176–1192 kg dan flow 2,39–2,50 mm. parameter volumetrik seperti vim, vma, dan vfa juga masih memenuhi spesifikasi. namun, pada kadar ask yang lebih tinggi, stabilitas dan mq cenderung menurun. hasil uji durabilitas menunjukkan nilai index of retained strength (irs) sebesar 75,68%, yang belum memenuhi persyaratan bina marga (≥90%), namun telah memenuhi standar aashto (≥75%). kombinasi kao 5,37%, pet ±5%, dan ask 25% memberikan kinerja terbaik, meskipun masih diperlukan peningkatan durabilitas.

The utilization of coconut fiber ash (CFA) and Polyethylene Terephthalate (PET) plastic waste in asphalt concrete wearing course (AC-WC) mixtures presents a potential approach to improve pavement performance while promoting sustainable material use. This study aims to analyze the effect of PET and CFA addition on Marshall characteristics and durability, as well as to determine the optimum composition in accordance with the General Specifications of Bina Marga 2018 Revision 2 (2020). The initial stage involved determining the Optimum Asphalt Content (OAC), which was obtained within the range of 5.03%, 5.37%, and 5.71%. All OAC values were then used in Marshall testing with PET variations of 5%, 7%, and 9% by weight of asphalt. The results indicated that a PET content of approximately 5% provided the best performance, with stability values ranging from 1174 to 1185 kg, flow values of 2.41–2.55 mm, and relatively high Marshall Quotient (MQ), indicating a good balance between strength and stiffness. Increasing PET content beyond 5% led to higher flow and lower MQ, suggesting increased plasticity and reduced stiffness. Subsequently, CFA was introduced as a filler at 25%, 50%, 75%, and 100% using the selected OAC and optimum PET content. The optimum composition was achieved at 25% CFA, with stability values of 1176–1192 kg and flow of 2.39–2.50 mm. Volumetric parameters, including VIM, VMA, and VFA, satisfied the required specifications. However, higher CFA contents resulted in decreased stability and MQ. Durability testing showed an Index of Retained Strength (IRS) of 75.68%, which does not meet Bina Marga requirements (≥90%) but satisfies AASHTO standards (≥75%). Therefore, the combination of 5.37% OAC, approximately 5% PET, and 25% CFA yields the best performance, although further improvement in durability is required.