ABSTRACT
Microsilica (MS), a by-product of smelting process in the silicon and ferrosilicon industry, is one of the most commonly used supplementary cementitous materials in concrete. Owing to its extreme fineness and high silica content, MS has been considered as an effective pozzolanic material to be used in concrete (Siddique, 2011). Since 1950, it has been used to replace some part of cement in concrete and the range has been 10-25% (Schröfl et al. 2012). It has been reported that the strength of concrete in which cement is replaced by 10% MS (by cement wt.) is more than the concrete without them (Mazloom et al. 2004, Wong & Razak, 2005, Poon et al. 2006). It has also been reported that the use of MS improves various durability properties of concrete (Poon et al. 2006).
