Mechanical performance, microstructure, and damage model of concrete containing steel slag aggregate

Abstract Reusing industrial solid waste in cement‐based products is an economical and environmentally friendly solution. This study investigated the effect of steel slag on the mechanical properties of concrete mixtures, and development of damage constitutive relationship of steel slag concrete (SSC). Two steel slag aggregates, including fine steel slag aggregate (SSA F ) and coarse steel slag aggregate (SSA C ) were incorporated into the concrete mixtures to SSC. The portions of natural sand and coarse aggregate each were replaced with SSA F and SSA C at 10%–100% (interval of 20%) by weight. Therefore, effects of SSA F and SSA C on the mechanical properties of SSC mixtures were evaluated separately. Moreover, damage model of SSC mixtures was developed based on Lemaitre's equivalent strain principle and Weibull probability density function. The damage constitutive model was revised using the functional relationship between the toughness index, brittleness index, and distribution parameters. The results indicate that SSC's mechanical properties, crack resistance, and toughness have been significantly improved with increased steel slag content. However, reduction in strength was observed in the SSC specimens containing steel slag above 50% replacement. Nevertheless, these strengths are higher than that of normal concrete. The modified damage constitutive relationship fits better with the experimental results.