The Ground Granulated Blast Furnace Slag (GGBS/GGBFS) is a type of eco-friendly green building material and high quality secondary cementitious material for concrete and cement. It is recognized as one of the best secondary cementations material for building high durable concrete stricture in the world today! GGBS has taken over a top place of high-performance cement and concrete mineral additives with its unique characteristics of hydration, low-price raw material. GGBS is obtained by quenching molten iron blast furnace slag (a by-product of iron and steel making) in water or steam. It is then further grounded into the desired fineness in terms of the required particle size distribution. The main components of blast furnace slag are CaO (30-50%), SiO2 (28-38%), Al2O3 (8-24%), and MgO (1-18%). The other important aspect of GGBS is its superiority in concrete durability which extends the lifespan of buildings from fifty years to a hundred years.