PENGARUH PENAMBAHAN SERAT SABUT KELAPA (COCONUT FIBER) TERHADAP KUAT TEKAN , KUAT TARIK BELAH DAN KUAT LENTUR PADA BETON - RIVALDO LUMBAN TOBING, GHARY; RISDIANTO, YOGIE (Rekayasa Teknik Sipil, 2019)
Abstrak Beton terdiri dari bahan campuran semen, kerikil, pasir, air dan bahan tambah. Penggunaan bahan tambah berupa serat alam yakni serat sabut kelapa diharapkan dapat memperbaiki sifat mekanik beton terkhususnya beton normal. Penelitian ini dimaksudkan untuk mengetahui komposisi penambahan serat sabut kelapa yang meningkatkan nilai kuat tekan, kuat tarik belah dan kuat lentur pada beton. Metode penelitian yang dilakukan adalah dengan merancang komposisi campuran beton untuk masing-masing tambahan serat serabut kelapa kemudian membuat sampel beton berbentuk silinder dan balok untuk kemudian dilakukan pengujian terhadap beton Penelitian ini menggunakan kuat tekan rencana f?c 24,90 N/mm2. Benda uji berupa silinder beton berukuran 15x30 cm dan balok beton berukuran 15x15x60 cm. Proses pengujian kuat tekan , kuat tarik belah, dan kuat lentur dilakukan pada umur beton 7 , 14, 21, dan 28 hari. Serat serabut kelapa sebagai bahan tambahan berupa serat dengan ukuran panjang 25-40 mm dan dengan persentase 2%, 4%, dan 6%. Hasil penelitian menunjukkan penambahan serat serabut kelapa 2% mempunyai pengaruh terhadap peningkatan kuat tarik belah dan kuat lentur, namun mengalami penurunan kuat tekan. Sehingga, kadar optimum penambahan serat serabut kelapa terhadap kuat lentur dan kuat tarik belah tertinggi terjadi pada penambahan sebesar 2% diperoleh rata-rata kuat tarik belah sebesar 2,38 MPa dan kuat lentur sebesar 5,705 MPa. Kata Kunci: beton serat, kuat lentur, kuat tarik belah, kuat tekan, serat serabut kelapa, ABSTRACT Concrete content consists of a mixture of cement, gravel, sand, water and added ingredients The use of natural fibers, namely coconut fiber, is expected to improve the mechanical properties of concrete, especially normal concrete. This study is intended to determine the composition of the addition of coconut fiber which increases the value of compressive strength, split tensile strength and flexural tensile strength in concrete. The research method is to design the composition of the concrete mixture for each coconut fiber addition and then produce cylinder and beam concrete samples to then test the concrete. This research using compressive strength plan f?c 24,90 N/mm2. The test specimen is a 15x30 cm concrete cylinder and a 15x15x60 cm concrete beam. The testing process of compressive strength, split tensile strength, and flexural tensile strength was carried out at 7, 14, 21 and 28 days of concrete. The proportion of fiber concrete mixture is 3 variations of stir. Coconut fiber as an additional material in the form of fibers with a length of 25-40 mm and with a percentage of 2%, 4%, and 6%. The results showed that the addition of 2% coconut fiber had an effect on the increase in split tensile strength and flexural strength, but experienced a decrease in compressive strength. Thus, the optimum level of coconut fiber addition to the highest flexural strength and split tensile strength occurred in an addition of 2% obtained by the average split tensile strength of 2.38 MPa and flexural strength of 5.705 MPa. Key words: coconut fiber, compressive strength, fiber concrete, flexural tensile strength, splitting tensile strength