PENGARUH HETEROGENITAS AGREGAT KASAR TERHADAP CAMPURAN BETON “THE INFLUENCE OF COARSE AGGREGATE HETEROGENEITY TO CONCRETE MIXTURE”

Abstract

nilai kuat tekan beton. Agregat kasar banyak tersedia dalam berbagai ukuran dan harga yang berbeda tiap ukuran. Tapi umumnya agregat kasar yang digunakan dalam campuran beton adalah agregat kasar ukuran 1/2. Namun ada kalanya karena sebab tertentu sehingga aggregate kasar tersebut terbatas jumlahnya tapi kebutuhan akan beton mendesak. Atau pada keadaan lain, pengguna menginginkan beton dengan harga yang lebih murah dengan kualitas baik. Atas dasar pertimbangan tersebut, dilakukan percobaan dengan mensubstitusi agregat kasar ukuran 1/2 dengan variasi ukuran batu pecah sejenis. Dengan percobaan ini, diharapkan mendapatkan solusi berupa beton dengan nilai ekonomis lebih menguntungkan dan kualitas yang baik. Benda uji yang digunakan berupa silinder dengan dimensi 300x150 mm dengan 3 variasi perbandingan agregat kasar. Variasi 1 (1/1 : 1/2 : 2/3 = 3 : 1 : 2), varisi 2 (1/1 : 1/2 : 2/3 = 5 : 1 : 3), dan variasi 3 (1/1 : 1/2 : 2/3 = 5 : 1 : 2). Hasil percobaan menunjukkan bahwa pada variasi 1 (1/1 : 1/2 : 2/3 = 3 : 1 : 2), varisi 2 (1/1 : 1/2 : 2/3 = 5 : 1 : 3), dan variasi 3 (1/1 : 1/2 : 2/3 = 5 : 1 : 2) kuat tekan dan tariknya mengalami peningkatan (variasi optimum pada variasi 3) Jadi didapat kesimpulan bahwa variasi ukuran agregat kasar dapat digunakan untuk mensubstitusi agregat kasar ukuran 1/2 dan meningkatkan kuat tekan dan tarik. Kata Kunci : beton, agregat kasar, heterogenitas, variasi optimum. vi “The Influence of Coarse Aggregate Heterogeneity to Concrete Mixture” ABSTRACT Coarse aggregate is a concrete mixture material which is very establish to compressive strength value of the concrete. Coarse aggregate is much available in many size and different price in each size. But generally coarse aggregate used in concrete mixture is coarse aggregate 1/2. However, sometimes because of certain reason that coarse aggregate is in limited amount but needs on concrete is urgent. Or on the other condition, the users want a cheaper concrete price with good quality. According to that consideration, an experimental study is performed by substitute coarse aggregate 1/2 with variation of another course aggregate size. With this experimental study, we expect to get a solution in the form of concrete with improved economic value and good quality. Experimental object used is 300 x 150 mm cylinder with three comparison variation of course aggregate. Variation 1 (1/1 : 1/2 : 2/3 = 3 : 1 : 2), variation 2 (1/1 : 1/2 : 2/3 = 5 : 1 : 3), and variation 3 (1/1 : 1/2 : 2/3 = 5 : 1 : 2). The result showed that at variation 1 (1/1 : 1/2 : 2/3 = 3 : 1 : 2), variation 2 (1/1 : 1/2 : 2/3 = 5 : 1 : 3), and variation 3 (1/1 : 1/2 : 2/3 = 5 : 1 : 2), the compression and tensile strength is increased (optimum variation in variaton 3).. So we can get a conclusion that variation of coarse aggregate size can be used for substitution and increase the compression and tensile strength. Keyword : concrete, coarse aggregate, Heterogeneity, optimum variation.