Microsilica or Silica Fume is a very effective pozzolanic material used to produce very dense, lower permeability concretes with few voids and greatly increased abrasion resistance.
It is a by-product from the production of ferrosilicon alloys. In conventional concrete, water reacts with the cement to form crystals, which grow and densify to bond aggregate particles together. Microsilica reacts with free lime to produce calcium silicate hydrate crystals which grow to fill the voids which would otherwise be occupied by pore water.
• Increases concrete density
• Increases compressive strength
• Improves mix cohesion
• Improves abrasion resistance
• Reduces permeability
• Reduces risk of ASR