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Abstract The global warming and the associated climatic changes have recently become a major concern due to its direct adverse effect on the earth‟s environment. One of the main reasons of the global warming is related to industries that emit CO2 to the atmosphere, the cement production industry alone participates by approximately 6 % from all the CO2 emissions worldwide. During the production of cement, CO2 is liberated as a result of de-carbonation of CaCO3. Researchers have found that the production of one ton of Portland cement liberates about one ton of CO2 to the atmosphere. In the construction industry, it is well known that cement is the primary binder in the concrete production and the production rate of cement is increasing annually, which means that if other alternative binders are not discovered, the CO2 emissions footprint will increase and accordingly the global warming and climatic changes will continue. The research work aims to study the mechanical properties and acid resistance of ground granulated blast furnace slag geopolymer concrete. The mechanical properties were studied in terms of compressive strength, tensile strength and modulus of elasticity whilst the acid resistance was studied in terms of weight loss and compressive strength loss. The ground granulated blast furnace slag geopolymer concrete is a type of concrete composed from a binder and aggregates where the slag is the main composition of binder instead of cement. During mixing the binder is formed by the reaction of slag and an alkaline solution made of a combination of sodium hydroxide and sodium silicate mixed with certain ratios. This type of concrete is one of the approaches that nowadays being developed in the search of an alternative binders than cement. The effect of sodium hydroxide molarity (10, 12 and 14 Moles), alkaline solution/slag content (0.40, 0.45 and 0.50), curing temperature (30°C, 60°C and 90° C), curing time (1, 2 and 3 days) and sodium hydroxide: sodium silicate (1:1.75, 1:2.50 and 1:3.25) were considered throughout the research program. The fractional factorial method of experimentation was used through the experimental program to reduce the number of mixes The results showed that in general the increase in molarity enhanced all of the properties, while the increase in alkaline solution/slag, curing temperature have adversely affected the geopolymer concrete whilst the best results of curing time has been achieved when the curing period is 2 days. Moreover, the increase in sodium hydroxide to sodium silicate ratio has enhanced the compressive strength, tensile strength, and modulus of elasticity. Moreover, the acid resistance weight loss reached the best value at sodium hydroxide: sodium silicate ratio of 1:2.5. |