The document summarizes the use of micro silica in concrete. It discusses that micro silica is a very fine mineral admixture that is 50-100 times finer than cement particles. When added to concrete, micro silica improves strength, durability, and impermeability. It works by both pozzolanic and micro filler effects - through chemical reactions with calcium hydroxide and by filling pores in the concrete respectively. The document outlines applications of micro silica concrete including high strength, corrosion resistance, heat reduction, and more. Testing showed replacement of up to 10% cement with micro silica increased compressive strength of M30 grade concrete.