Effect of Micro-Silica on Mechanical Strength of Concrete

This paper investigate the variation in compressive strength and tensile strength of concrete by using micro-silica. Micro-silica is used in partial replacement of ordinary Portland cement (OPC) by weight at 0 %, 2 %, 4 %, 6 %, 10 %. In this research M20 grade concrete was used in which material proportion was determined by design mix. Design mix by IS method was used for concrete cube and ACI design mix method used for Cylindrical sample to find out material proportion. Compressive strength test was carried out on 150mm concrete cube and tensile strength test was carried out on 100mm diameter& 200mm long cylinder by splitting test after 7, 14 and 28 days curing period. According to the experimental results, the compressive strength at 28 days ranged between 28.948MPa& 40.519MPa and Tensile strength at 28 days ranged between 2.707MPa& 5.361MPa. These indicate that 10 % micro-silica used in replacement of OPC increases the compressive and Tensile strength significantly.