EFFECTS OF SILICA FUME (MICRO SILICA OR NANO SILICA) ON MECHANICAL PROPERTIES OF CONCRETE: A REVIEW

In the present era very vast development occurred in the field of construction specially in concrete technology. Concrete is the most versatile material due to its continuous demand. Many researchers and scientists have been developed a no. of techniques to improve the parameters of concrete i.e. strength & durability. Engineers are continuously pushing the limits to improve the performance with the help of supplementary cementitious material like blast furnace slag, Flyash, steel slag, silica fume etc. The present research work focused on one of such product i.e. silica fume. Silica fume is an amorphous (non crystalline) polymorph of silicon oxide. It has its forms also i.e. micro silica (MS) and nano silica (NS). It is ultrafine powder with an average particle size of 0.1 to 0.5 ?. Silica fume is pozzolainc material and is available in different forms. The past investigations reveled that silica fume is an excellent pozzolanic material in producing high performance concrete (HPC). In this review paper we will study the effect of MS and NS in the concrete properties with their different different percentages in the different grades of concrete. Nano technology is most promising area of science. It is revolution in construction industry. Different nano materials like nano silica, nono titanium oxide, carbon nano tube etc. are now a days used by the engineers in construction work. Nano silica and micro silica particles sizes are very very small so they can fill the pores or small spaces of concrete easily and effectively. Thus there is a scope for cracks free concrete towards the crack free sustainable construction. So here in the article we will discuss about the silica fume and its forms i.e. micro silica and nano silica and their effects on the properties of the concrete. It is found from the previous studies that the combine use of the pozzolan i.e. MS & NS can produce superior properties.