PENGARUH JENIS SEMEN DAN JENIS AGREGAT KASAR TERHADAP KUAT TEKAN BETON

Abstract

The effect of cement and coarse aggregate type on compressive strength of concrete is investigated by using the cube specimens 150 ´ 150 ´ 150 mm. Specimen made with the comparison of weight to obtain a mixture cement as follows: fine aggregate compared to coarse aggregate in ratio of 1.0: 1.4: 2.1 with water cement factor of 0.42. The type of cement used in this research are portland cement type I, portland pozzolan cement, and portland cement composite. The coarse aggregate consist of pebbles and crushed stone with a maximum diameter of 20 mm. Com­pressive strength examinations was conducted at 3, 7, 28 and 90 of the days. The research results showed that the development speed of compressive strength is mostly influenced by chemical properties, physical properties, and the type of additive anorganic materials. The effect of coarse aggregate on concrete strength is apparent until the hydration at 28 of days and after this period the effect went to weaken.

Pengaruh jenis semen dan jenis agregat kasar terhadap kuat tekan beton diteliti dengan menggunakan benda uji kubus 150 ´ 150 ´ 150 mm. Benda uji dibuat dengan perbandingan berat campuran semen : agregat halus : agregat kasar 1,0 : 1,4 : 2,1 dengan faktor air semen sebesar 0,42. Semen yang digunakan adalah semen portland tipe I, semen portland pozzolan, dan semen portland komposit. Agregat kasar berupa kerikil dan batu pecah dengan diameter maksimum 20 mm. Ujian kuat tekan dilaksanakan pada umur 3, 7, 28, dan 90 hari. Hasil pengujian menunjukkan bahwa kecepatan perkembangan kuat tekan yang dihasilkan banyak di­pengaruhi oleh properti kimia, fisik, dan serta jenis bahan anorganik yang ditambahkan. Pengaruh jenis agregat kasar terhadap kekuatan beton tampak jelas hingga mencapai umur hidrasi 28 hari, setelah periode tersebut pengaruhnya cenderung melemah.