Effects of electric arc furnace (EAF) slags on mechanical and permeability properties of paving stone, kerb and concrete pipes

Abstract

In this study, the usage of electric arc furnace slag obtained as waste from the steel industry in the production of various concrete elements instead of natural aggregates was investigated. Although there are many studies on the use of EAF aggregates in concrete, studies on the use of these aggregates in the production of industrial concrete elements are very limited. In this context, the physical properties of EAF aggregates, which were separated in natural aggregate size, were determined and compared with natural aggregates. In the second part of the study, different ready-mixed concrete and dry consistency (zero slump) concrete mixtures were produced with natural aggregates and EAF slags in the laboratory, and the fresh and hardened concrete properties of these concrete mixtures were determined. In the last part, studies on the usage of EAF slags in the production of paving stones, concrete paving flags, kerbs and concrete pipes instead of natural aggregates were performed to the related product standards. It was determined that the splitting tensile strength of the paving stones produced with EAF slag was 4.5 MPa, the flexural strength of the paving flags was 5.3 MPa, the bending strength of the kerbs was 6.3 MPa. Abrasion values of all concrete elements varied between 19 and 22 mm. In addition, it has been determined that the structural ultimate load-carrying capacity of the concrete pipes is 252 kN/m and higher than the reference products. The water absorption values of paving stones and kerbs were lower than reference products and the hydrostatic performance of the pipes produced with EAF aggregates was sufficient for watertightness. These values correspond in most cases to the highest bending and abrasion classes in the relevant product standards. As a result of the studies, industrial elements such as paving stones, flags, kerbs, and concrete pipes can be produced with the desired properties in the related standards by using EAF aggregates. Thus, it is possible to contribute to the effective use of natural resources and sustainability by producing high-performance concrete elements by using EAF aggregates.