Ground-granulated blast-furnace slag (GGBFS or GGBS) is obtained by quenching molten iron slag (a by-product of iron and steel-making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder.
The main components of blast furnace slag are CaO, SiO2, Al2O3 and MgO.
GGBFS is used to make durable concrete structures in combination with ordinary portland cement and/or other pozzolanic materials.Use of GGBFS significantly reduces the risk of damages caused by alkali–silica reaction (ASR), provides higher resistance to chloride ingress — reducing the risk of reinforcement corrosion — and provides higher resistance to attacks by sulfate and other chemicals.

Ground-granulated blast-furnace slag (GGBFS or GGBS) is obtained by quenching molten iron slag (a by-product of iron and steel-making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder.
The main components of blast furnace slag are CaO, SiO2, Al2O3 and MgO.
GGBFS is used to make durable concrete structures in combination with ordinary portland cement and/or other pozzolanic materials.Use of GGBFS significantly reduces the risk of damages caused by alkali–silica reaction (ASR), provides higher resistance to chloride ingress — reducing the risk of reinforcement corrosion — and provides higher resistance to attacks by sulfate and other chemicals.