The Effect of Using Silica Fume on Medium Strength Concrete

Silica fume is a fine powder additive consisting of amorphous microspheres with diameters ranging from 0.1 to 0.2 μm, which important role in the concrete chemical and mechanical properties effect. Mechanical properties when viewing on geometrically, silica fume is known as a pozzolanic material to fill the cavities on the concrete material. In this paper, to determine the optimum composition of using the silica fume on medium strength concrete from Kampar district local materials, Riau Province. The design of this study used 20 Mpa strength concrete with the addition of silica fume. The used amounts of silica fume content to increase mechanical properties are 0–15% from concrete weight and there is 24 pieces sample. The concrete compressive strength test was carried out at 14 and 28 days of soaked, and the test object uses a cylinder. This test on concrete soaked representing each design age. The results of this study, the addition of silica fume has the optimum composition of 5% for 14 days of age, the compressive strength of the concrete is 31 MPa. And for 28 days of age, the compressive strength of concrete is 26 Mpa.