Penggunaan beton sebagai bahan bangunan telah lama dikenal. beton merupakan material komposit yang tersusun dari agregat dan terbungkus oleh matrik semen yang mengisi ruang di antara partikel-partikel sehingga membentuk satu kesatuan. berdasarkan kuat tekannya beton dibagi menjadi tiga klasifikasi, yaitu beton normal, kinerja tinggi, dan kinerja sangat tinggi. penelitian ini dilakukan dengan memanfaatkan serat sabut kelapa sebagai bahan tambah pada campuran beton, penambahan serat sabut kelapa dalam beton normal tentu memiliki cara analisis tersendiri. penambahan serat dalam proporsi tertentu kemungkinan dapat mempengaruhi perilaku struktur beton secara keseluruhan, persentase penambahan serat 0% (a00), 0,33% (a30), 0,35% (a35), 0,4% (a40) dan 0,45% (a45). penelitian ini menggunakan benda uji berdimensi 15 x 15 x 15 dengan umur pengujian kuat tekan 7, 14, 21, 28 hari dan jumlah kubus 60 sampel. dari hasil kuat tekan yang diperoleh pada umur optimum pada 28 hari didapat kuat tekan pada variasi campuran kode sampel a00 : 275,15 kg/cm2, umur kuat tekan beton optimum 28 hari a30 : 278,78 kg/cm2, umur kuat tekan beton optimum 28 hari a35 : 279,23 kg/cm2, umur kuat tekan beton optimum 28 hari a40 : 279,83 kg/cm2 , umur kuat tekan beton optimum 28 hari a45 : 279,99 kg/cm2 dari penambahan persentase serat 0%, 0,3%, 0,35%, 0,4% dan 0,45% diperoleh 0,45% memiliki kuat tekan tertinggi.

The use of concrete as building material has long been known. concrete composite material is composed of aggregates in cement matrik and fills spaces between particles so as to form a single entity. on the basis of strong concrete press it divided into three classifications, namely the normal concrate, a high performance, and performance is very high the research was conducted by using a coconut fibers add on a mixture of concrete, the addition of fibers from the normal way in a concrete certainly has its own analysis.the addition of fiber in specific proportions of possibilities influence behavior of concrete structure as a whole , the percentage of the additional fiber 0 % (a00), 0,3 % (a30), 0,35 % (a35),0,4 % (a40), and 0,45 % (a45). this study uses the test specimen dimension 15 x 15 x 15 cube with age compressive strength testing of 7, 14, 21, 28 days and total cube 60 samples. compressive streght of the results obtained at the optimum age of 28 days compressive strength ontained on the variation of the code samples a00: 275,15 kg/cm2, the age of compressive strength concrete said 28 days a30: 278,78 kg/cm2, the age of compressive strength concrete said 28 days a35: 279,23 kg/cm2, the age of compressive strength concrete said 28 days a40: 279,83 kg/cm2 , the age of compressive strength concrete said 28 days a45: 279,99 kg/cm2. from the addition of the percentage fibers 0%, 0.3%, 0.35%, 0.4% and 0.45% obtained 0.45% has the highest compressive strength