Electric Arc Furnace Slag As a Retaining Wall Material in Concrete

Electric Arc Furnace Slag As a Retaining Wall Material in Concrete

The production of steel by electric arc furnaces produces a significant amount of waste material called slag.electric furnace slag retaining wall This slag is classified as non-hazardous material and can be reused in various construction contexts. One of these is the use of slag as aggregate for self-compacting concrete, as demonstrated in the BedZED building and the Angus Technopole. However, further research is required to demonstrate its suitability in road construction.

The slag generated by the EAF process contains up to 15% silica.electric furnace slag retaining wall The slag can be mechanically recycled by a crushing and screening process. This process yields coarse and fine slag aggregates, and the slag powder can be further ground to obtain granulated slag for use in concrete. Its high density, resistance to segregation and low permeability make it an ideal aggregate for self-compacting concrete. In addition, the slag exhibits excellent durability and can resist corrosion. It is also possible to use it in the formation of a new slag type – slag clinker – for use as a cement replacement.

An investigation was conducted to determine the effect of varying the size of granulated slag on its behavior as an SCM in concrete and mortar mixes.electric furnace slag retaining wall Four different groups of samples were tested, including control mortars, mortar mixes containing granulated slag of different sizes and fly ash replacement levels and mortar mixes incorporating granulated slags of optimum fineness. The samples were characterized by their physical properties, which were evaluated through compressive strength tests on 50 mm cubes.

Results showed that the slags, if activated by means of mechanical grinding and calcination, exhibited greater activity than the reference concretes. The slag-fine (SF) and slag super-fine (SSF) exhibited greater activity than the coarse slag aggregate, despite having similar particle size distributions. The SF and SSF were also found to form a more cohesive paste than the coarse slag, resulting in lower mortar slump and passing ability. The slag also had excellent pozzolanic reactions, which resulted in higher shear and tensile strengths.

The gd,max and wopt of the slag-fine and slag-super-fine were significantly higher than those of the control and fly ash mixes. In general, slag-fine and slag-super-fine displayed superior performance in terms of permeability and shear strength, although they did not perform as well as the coarse slag aggregate. In particular, the SSF showed the best pozzolanic reaction and lowest water absorption values. This is due to the fact that the slag granules have better interlocking between each other than those of the coarse aggregates, which is the reason for the decrease in their swelling ratio after 96 h. Moreover, the slags exhibited a more even PSD in comparison to the coarse aggregates, which contributed to their better interlocking and reduced permeability. This was confirmed by the SEM images, which indicated a better distribution of the fine slag particles and a smoother surface. These findings indicate that it is possible to produce a self-compacting concrete using slag aggregates and to reduce the cement content without sacrificing strength and economy.

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