Asphalt concrete using mineral powder based on electric steelmaking slag

The use of electric steelmaking slag in road construction allows decreasing the cost of the produced products, and solves an important environmental problem by reducing the areas occupied by dumps. In laboratory conditions, recipes for using the electric steelmaking slags as crushed stone, sand, and mineral powder for asphalt concrete are most often developed without taking into account the effect of shelf life in dumps on the properties of slag materials. During the long-term storage of slag, its phase composition changes, so the use of mineral powder based on electric steelmaking slag of current output and slag stored in dumps for more than 5 years requires preliminary analysis of its properties. IR spectra of bitumen were recorded after their interaction with mineral materials based on electric steelmaking slags of various shelf life in dumps. The physical and mechanical characteristics of asphalt concrete were examined with the introduction of slag mineral powder into its composition, and recommendations were provided for using electric steelmaking slags in road construction, taking into account the aging processes occurring during the slag storage in dumps. According to IR spectroscopy, the storage time of slag in dumps does not significantly affect the diffusion of bitumen light fractions into the pores of the slag mineral material. When using electric steelmaking slag as a mineral powder for asphalt concrete, current-output slag and slag stored in dumps for several years behave similarly. The most effective approach is to use current-output slag as a mineral powder.