Durability Aspects Study of GGBS and Crusher Sand based High Performance Concrete

Concrete made from ordinary Portland cement continues to be used as one of the primary material because of its durability and strength characteristics in service life. But the contrary becomes the case when such concrete is exposed to aggressive environment created by the prevalence of chloride ions that are common in marine/coastal environment characterized by temperature extremes, that is peculiar to India. Same time, present global environmental requirements suggest the civil engineers for reducing the consumption of OPC. Use of mineral admixtures like Blast Furnace Slag, Fly Ash and Silica Fume etc. in concrete may be a suitable solution in such situation. Hot marine and coastal environment with large variations in temperature, constitute an aggressive environment that has been found to be deleterious to the strength and durability characteristics of concrete, thus causing premature deterioration of concrete structures. Research works to reverse this trend go on continuously. This paper presents one of such works which investigates the effect of partial replacement of cement with slag and replacement of normal river sand with crusher dust for concrete preparation. The specimens cured at elevated temperatures were studied for all the durability criteria at the optimized crusher sand percentage. It discusses the resistance of GGBFS blended concrete to Chloride attack, Sulfate attack, Carbonation, Aggregate-Silica reaction and Frost attack with factors influencing its performance. It was found out that partial replacement of cement with slag increases the resistance of concrete to chloride penetration. The durability of HPC specimens was evaluated on the basis of reduction in compressive strength when exposed in Sulfuric acid (pH=5) solution for 28 days. Specimens containing lesser alkali were found to have lower water absorption as compared to normal concrete.