Fly ash is a byproduct of coal production and can be used to replace some of the cement content in a concrete mix. It can also increase the workability, strength, and overall chemical resistance of concrete.
Slag can be used in combination with cement to reduce permeability in concrete. Over time, slag continues to develop strength and can help concrete become less vulnerable to corrosion.
When used in combination with cement, Microsilica contributes to concrete strength by decreasing permeability, which in turn helps guard against damage caused by freeze-thaw cycles.