Since we know that silica fume, fly ash, copper slag, etc are waste materials that cause environmental problems. So reuse of this
materials from industries have been increased, this materials can be used to produce new products or can be used as admixtures so
that natural resources are used more effectively and can protect environment from this waste materials.
Silica fume is produced by a byproduct of silicon metal or ferrosilicon alloy. Silica fume is mostly used in replacement of cement as
a binder.
Because of its chemical and physical properties, it is very reactive pozzolan. Concrete containing silica fume contain high strength
when it is mixed in concrete and is durable too. The physical composition of silica fume diameter is about 0.1 micron to 0.2 micron
and surface area is about 30,000 m2
/kg.
Silica fume improves the long term corrosion resistance and alkali silica increases expansion but also increases the carbonation of
depth and reduces heat of hydration.