GGBFS is a byproduct of iron ore smelting in a blast furnace. It consists of silicates and aluminosilicates, the chemical composition depends on the composition of the iron ore, while the physical properties depend on the cooling process.  Slag cement is produced when GBFS is ground very fine to partially replace Portland cement, resulting in the following advantages:

• Increase sulfate resistance
• Increase alkali-silica reaction resistance
• Increase pore refinement
• Decrease water demand
• Decrease permeability
• Increase long-term strength
• Less heat of hydration