Abstract
Linz-Donawitz (LD) slag, solid waste produced during steel manufacture in basic oxygen furnace, is difficult when it comes to handling and disposal and has very limited utilization. To increase its reusability, the suitability of supplanting cement with LD slag in concrete was examined. To study the impact of partially replacing cement with LD slag on strength, microstructure, and durability of concrete, more than 150 samples were cast. The test results reveal that the highest compressive and flexural strengths were attained at 20% LD slag replacement and, beyond that, the strength decreased. The hydration products detected by X-ray Diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) were calcium silicate hydrate (C-S-H), ettringite, and calcium aluminosilicate hydrate (C-A-S-H). The scanning electron microscope (SEM) images of binary cement concrete showed denser microstructure and lesser voids. The sulphuric acid resistance, electrical resistivity, and carbonation resistance tests done reveal that acceptable durability could be achieved when cement is replaced by LD slag. It is deduced that LD slag can be utilized in partially replacing cement to achieve the desired strength. This research gives another comprehension of simultaneously managing steel industry waste for sustainable development and contributing added advantages to the economy.
Highlights
Introduction e substantial growth in theIndian steel industry in recent times has led to massive and varied solid wastes generation
Blast furnace slag and steel furnace slag (LD slag and electric arc furnace slag) comprise the majority of waste slag generated during the manufacturing of iron and steel, respectively
After a curing period of 28 days at room temperature, the samples were kept inside the carbonation chamber and the parameters mentioned above were maintained throughout the test
Summary
To evaluate the degree of hydration, the samples hydrated for 7 and 28 days, respectively, were tested for their nonevaporable water content (Wn). e samples (hardened pastes) were heated at a temperature of 65°C for a period of 24 hours in an oven. ey were heated in a muffle furnace at 1000°C for 2.5 hours. To evaluate the degree of hydration, the samples hydrated for 7 and 28 days, respectively, were tested for their nonevaporable water content (Wn). E samples (hardened pastes) were heated at a temperature of 65°C for a period of 24 hours in an oven. E test was performed on the concrete samples of all varying mixes cured for 7, 14, and 28 days, respectively. After 28 days of curing, the initial mass of cubes was noted before immersing in the acid solution. After a curing period of 28 days at room temperature, the samples were kept inside the carbonation chamber and the parameters mentioned above were maintained throughout the test. E average value of three cubes was taken to determine the bulk electrical resistivity of the concrete A wet sponge is placed on top of the cube and current is passed through the electrodes. e average value of three cubes was taken to determine the bulk electrical resistivity of the concrete
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
