Pengaruh Substitusi 15% Bio-oil Limbah Cangkang Pala Terhadap Kinerja Indirect Tensile Test Campuran AC-WC

Farrel Todotua Tarihoran, Ir. Latif Budi Suparma, M.Sc., Ph.D.

2026 | Skripsi | TEKNIK SIPIL

Infrastruktur jalan di Indonesia memegang peranan krusial dalam mendukung kelancaran logistik dan pergerakan masyarakat. Akan tetapi, kesenjangan kualitas jalan merupakan isu nasional yang belum selesai. Permasalahannya adalah aspal sebagai material pengikat dalam perkerasan memiliki sifat yang tidak berkelanjutan. Menanggapi isu tersebut, studi ini diorientasikan untuk menganaisis dampak pemanfaatan bio-aspal berbasis limbah cangkang pala (nutmeg shell bio-asphalt) terhadap karakteristik Marshall dan Indirect Tensile Test (ITS) pada campuran Asphalt Concrete-Wearing Course (AC-WC).

 

Penelitian ini dilaksanakan Laboratorium Transportasi DTSL FT UGM dengan merancang campuran AC-WC kontrol dan campuran yang telah disubstitusi dengan 15% nutmeg shell bio-oil (NSBO). Melalui pengujian Marshall, diperoleh hasil analisis void in mineral aggregate (VMA), Void in mixture (VIM), void filled with asphalt (VFA), stabilitas, dan kelelehan. Selanjutnya, pengujian ITS dilakukan pada kadar aspal optimum setiap variasi dengan menganalisis parameter moisture sensitivity dan thermal sensitivity pada temperatur 40°C dan 50°C.

 

Hasil analisis menunjukan bahwa penambahan 15% nutmeg shell bio-oil mempengaruhi karakteristik Marshall, moisture sensitivity, dan thermal susceptibility. Dari karakteristik Marshall, didapat bahwa dalam beberapa parameter, campuran dengan substitusi bio-oil sebanding atau lebih baik dari pada campuran kontrol. Dari karakteristik tersebut, KAO campuran bio-oil lebih tinggi dengan nilai 6,2% dibandingkan dengan campuran kontrol dengan nilai 5,6%. Pengujian ITS juga menunjukan campuran substitusi bio-oil memiliki moisture sensitivity yang lebih baik dengan hasil ITS conditioned 1189,5 kPa, unconditioned 1274,2 kPa, dan nilai TSR 93,4% dibandingkan campuran kontrol dengan hasil ITS conditioned 986,6 kPa, ITS unconditioned 1132,4 kPa, dan nilai TSR 85,5%. Selain itu, campuran bio-oil menunjukan sifat thermal susceptibility yang lebih baik pada suhu 40°C dan 50°C dengan nilai ITS rata-rata masing-masing 342,4 kPa dan 236,7 kPa dibandingkan campuran kontrol dengan nilai 313,8 kPa dan 173,8 kPa.

Road infrastructure in Indonesia plays a crucial role in supporting smooth logistics and public movement. However, the disparity in road quality remains an unresolved national issue. The core problem is that asphalt, as a binding material in pavements, possesses non-sustainable properties. In response to this issue, this study is oriented toward analyzing the impact of utilizing bio-asphalt based on nutmeg shell (nutmeg shell bio-asphalt) on the Marshall characteristics and indirect tensile strength of Asphalt Concrete-Wearing Course (AC-WC) mixtures.

 

This research was conducted at the Transportation Laboratory, DTSL FT UGM, by designing a control AC-WC mixture and a mixture substituted with 15% nutmeg shell bio-oil (NSBO). Through Marshall testing, analytical results were obtained for voids in mineral aggregate (VMA), voids in total mixture (VIM), voids filled with asphalt (VFA), stability, and flow. Furthermore, ITS testing was performed at the optimum asphalt content of each variation by analyzing moisture sensitivity and thermal sensitivity parameters at temperatures of 40°C and 50°C.

 

The analysis indicated that incorporating 15% nutmeg shell bio-oil influenced the Marshall characteristics, moisture sensitivity, and thermal susceptibility. Regarding Marshall characteristics, revealed that in several parameters, the mixture with bio-oil substutition matched or exceeded the baseline mixture accross several indicators. Based on these characteristics, the optimum asphalt content (OAC) of the bio-oil mixture was higher at 6.2% compared to the control mixture at 5.6%. ITS testing also demonstrated that the bio-oil substituted mixture exhibited better moisture sensitivity, with a conditioned ITS of 1189.5 kPa, an unconditioned ITS of 1274.2 kPa, and a Tensile Strength Ratio (TSR) value of 93.4%, compared to the control mixture which had a conditioned ITS of 986.6 kPa, an unconditioned ITS of 1132.4 kPa, and a TSR value of 85.5%. Furthermore, the bio-oil mixture showed better thermal susceptibility properties at 40°C and 50°C, with average ITS values of 342.4 kPa and 236.7 kPa, respectively, compared to the control mixture values of 313.8 kPa and 173.8 kPa.

Kata Kunci : Bio-oil, Cangkang Pala, AC-WC, Karakteristik Marshall, Indirect Tensile Strength