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What is silica fume?

Q. What is silica fume?


A. Silica fume is very fine noncrystalline silica produced in electric arc furnaces as a byproduct of the production of elemental silicon or alloys containing silicon.(ACI CT). The average size of a silica fume particle is about 100 times smaller than an average portland cement particle. It acts as a mineral filler and also as a pozzolan, leading to concrete of high strength and low permeability. Silica fume is marketed in different forms: as-produced, densified or compacted, and slurried.


References: SP-1(02); ACI CT-23; ACI 234R-06; E3-13; ASTM C1240

Topics in Concrete: Silica Fume; Concrete Fundamentals; Materials; Pozzolan

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