This study investigates the effect of Local Ground Granulated Blast Furnace Slag (GGBS) with and/or without chemically 
activators on chloride ingress in hardened OPC Mortar. The used GGBS replaced OPC by 10 and 20%. Three different 
types of alkali-based chemical activators (sodium silicate, sodium carbonate and lithium hydroxide) were used with the 
OPC mix containing 20%GGBS. Chloride ingress was assessed by measuring Chloride Penetration Test, as a function of 
depth (chloride profile). To broaden the understanding, compressive strength, TGA and MIP were conducted. The results reveal that, chloride ingress resistance decreased with increasing local GGBS replacement level without using chemical 
activators. However; the effect can be enhanced by using chemical activator. The used chemical activators with 20%
GGBS mix improve its microstructure. The use of lithium hydroxide as a chemical activator improves chloride ingress 
resistance for 20% GGBS mix higher than the other used activators (sodium silicate, sodium carbonate).