Response of Silica Fume Based Low Strength Concrete to Acid Attack

چکیده مقاله

Traditionally, concrete has been considered as a basic material to build our schools, hospitals, homes, bridges, sewage systems, roads and more. Aggressive environment in sewage system and groundwater may cause damage to the concrete in underground structures. In this paper, laboratory tests were performed to assess the damages of acid attacks using a mixed solution of sulfuric and nitric acid on low strength concretes (LSC). The selected solutions were determined by consideration of the sewage system in Al-Nassiriya city in south of Iraq. The main parameter investigated in this study was M15 grade concrete with partial replacement of cement by silica fume by 0, 4, 8, 15, and 20%. The performance of the degraded specimens was evaluated by measuring the weight loss, change in strength and visual assessment. Test results indicated that the LSC with 15% of silica fume had higher values of compressive strength. The results also noted that the mixture with silica fume had less weight loss than the reference mix with only Portland cement. However, concrete mixtures experienced the highest strength loss after exposure to aggressive acid solutions for different periods of time.