Effects of Silica Fume in Conventional Concrete

The production of tailor made high strength and high performance concrete are made by incorporating silica fume into the normal concrete and it is a routine one in the present days. The mix proportioning is intricate and the design parameters are increased due to the incorporation of silica fume in conventional concrete. The aim of this paper is to look into the different mechanical properties like compressive strength, compacting factor, slump of concrete incorporating silica fume. In this present paper concrete incorporating silica fume are cast for 5 (five) mixes to perform experiments. Different percentages of silica fume are used for cement replacement in order to carry out these experiments at a single fixed water-cementitious materials ratio keeping other mix design parameters constant. The cement replacement level by silica fume was 0%, 5%, 10%, 15% and 20% for a constant water-cementitious materials (w/cm) ratio for 0.50. 100 and 150 mm cubes are used to determine the compressive strengths for all mixes at the age levels of 24 hours, 7 and 28 days. Besides the compressive strengths other properties like compacting factor, slump of concrete are also determined for five mixes of concrete.