Table 1.

Chemical composition (% by mass) of GGBS and OPC.

Component	GGBS	OPC
Silicon dioxide (SiO2)	34.7	20.9
Aluminium oxide (Al2O3)	13.8	5.39
Calcium oxide (CaO)	40.1	64.7
Iron oxide (Fe2O3)	0.11	2.38
Magnesium oxide (MgO)	4.38	1.51
Titanium dioxide (TiO2)	0.74	1.33
Sodium oxide (Na2O)	0.20	0.27
Potassium oxide (K2O)	0.48	0.22
Sulfur trioxide (SO3)	4.83	1.65
Loss on ignition (LOI)	2.70	5.80
Basicity coefficient (Kb)	0.92	2.52
Hydration modulus (HM)	1.68	3.43

Notes: K_b = (CaO + MgO)/(SiO₂ + Al₂O₃); HM = (CaO + MgO + Al₂O₃)/SiO₂.