Influence of nano-blast furnace slag on microstructure, mechanical and corrosion characteristics of concrete

In this study, the influence of nano-blast furnace slag (NBFS) on microstructure, mechanical and corrosion characteristics of concrete has been evaluated. The cement was replaced with NBFS at different percentages of 1, 2, 3, 4 and 5% by weight of cement. X-ray diffraction (XRD) and scanning electron microscope (SEM) connected with energy dispersive X-ray unit (EDS) were used to examine the microstructure characteristic of the different samples. The compressive strength, capillary water absorption and thermal analysis of the hardened concretes were evaluated according to ASTM standards. The corrosion resistance of the steel bar imbedded in concrete was assessed using different electrochemical techniques. The results of XRD and SEM examinations showed that incorporating NBFS into the concrete remarkably diminished the intensities of portlandite peaks and a dense structure was obtained. Further, significant enhancements in the mechanical properties, durability and corrosion resistance were attained with increasing NBFS in the concrete.