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This paper explores the effects of nano-kaolinite clay (NKC) on the behavior of concrete, when exposed to an acidic, chloride, and freeze-thaw environment.Ordinary Portland cement was partially substituted with NKC in ratios of 0%, 1%, 3%, and 5% by weight.The chloride diffusion property of cement mortar and concrete was investigated by rapid chloride migration (RCM) method.To simulate acid deposits, a sulfate and nitric acid solution with a pH level of 1.5 was deposited in the cement mixture in our laboratory experiments.The Rapid Freeze-Thaw Cabinet was used to measure the resistance of ordinary concrete and concrete with NKC to deterioration caused by repeated F-T actions.Properties (including the pore structure, mass, electrical resistivity,compressive strength and dynamic modulus of elasticity) of the concrete were measured at regular intervals.It is revealed that the chloride diffusion coefficient of concrete is decreased exponentially with the NKC additives.The results showed that both the mass and compressive strength of the NKC added mortars were higher than the control specimens after 20, 40 and 60 days exposure to the acid solution.The experimental results revealed that the introduction of NKC improves the F-T resistivity values, as compared to the control concrete.