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Abstract This work investigates properties and applications of alkali activated cements by studying strength and durability characteristics of ground granulated blast furnace slag (GGBFS) Concrete. Different properties of (GGBFS) concrete were studied using ground granulated blast furnace slag (GGBFS), Ordinary Portland Cement (OPC), silica fume, gypsum and lime stone in different mix proportions. Trail mixes were carried out to reach mix proportions of experimental work. Five mixes with variable percentage of cement replacement with (GGBFS) of mixtures up to 45% were carried out. The effect of partial replacement of Ordinary Portland Cement (OPC) by ground granulated blast-furnace slag (GGBFS) , silica fume , lime stone , gypsum was investigate on the various properties of concrete. Durability of concrete was investigated through the exposure of test specimens to sulphuric acid solution. Reinforced concrete members were cast to study the behavior of reinforced (GGBFS) concrete under different loads. Using high percentage of GGBFS; consistency flow ability increases but strength decreases at same water content. M1 (100 OPC) gained slump 72%, 72%, 51% and 60% of M2 (75% OPC and 25% GGBFS), M3 (75% OPC, 20% GGBFS and 5% S.F), M4 (05% OPC, 45% GGBFS and 5% S.F) and M5 (50% OPC, 30% GGBFS, 10% S.F, 5% Lime stone Powder and 5% Gypsum) respectively. The concrete containing GGBFS has low early-ages strength, but shows high later strength at 90 days. M3 achieved highest compressive strength at all ages. After 3 days M3 had compressive strength 248 Kg/cm2, while compressive strength of M1 was 88% of M3 (217.8 Kg/cm2). At 7 days age, compressive strength of M3 rose to 305.8 Kg/cm2. M1 had 77% of compressive strength M3 (234.5 Kg/cm2). At 28 days age, M3 achieved compressive strength 356.8 Kg/cm2, M1 had 88% of compressive strength M3 (313.5 Kg/cm2). Test results for 90 days showed that compressive strength of control mix compared to M3 compressive strength was 87%. This means the rate of strength gain is steady. Exposure of test specimens to sulphuric acid solution control mix had higher degradation percent in compressive strength after 28 day and loss mass was higher than that of GGBFS mixes. After 28 days, M1had degradation percent in compressive strength12.2%, while M3 had 4.2%. After 90 days, M1had degradation percent in compressive strength 18.1%, while M3 had 10.1%. Load vs. displacement curves for the GGBFS reinforced concrete members shows good ductility than that of control mix. At 28 days, M1 had ductile index 1.13, while M3 had ductile index 20.93. At 90 days, M1 had ductile index 3.74, while M2 had ductile index19.8. Ground granulated blast furnace slag (GGBFS) Concrete is a sustainable building material, which may be used as environmental friendly construction material. |