The paper discusses the mix design of skid resistance asphalt concretes made using Electric Arc Furnace (EAF) steel slags, produced in Italian steel plants, in partial substitution of the natural lithic matrix.
The study, conducted at the Experimental Road Laboratory of the University of Padova, has been articulated in a preliminary investigation on the chemical, physical, and mechanical properties of the EAF steel slag, and in the following Marshall mix design and Indirect Tensile Strength evaluation of five different skid resistance bituminous conglomerates, characterized by different steel slags content, up to the 35% of the aggregate weight.
The comparison between the steel slags and a conventional crushed limestone, in terms of the most significant road engineering properties, has demonstrated several superior characteristic of the steel slags; moreover its leaching behaviour resulted absolutely not hazardous.
All the mixtures with EAF slags have satisfied the requisites for acceptance in the road sector technical standards (Marshall Stability, Marshal Quotient and Indirect Tensile Strength up to 905 daN, 203 DaN/mm and 1.06 MPa, respectively, depending on the mixture), thus resulting as suitable for use in the construction of high skid resistance wearing course for road infrastructures, moreover presenting higher mechanical characteristics than those of the corresponding asphalts with full natural aggregate.
