## Materials and Methods  
### Materials  
Standardized siliceous sand, CEM I 52.5 R and cupola slag have been used for the manufacture of conventional mortars. For the manufacture of the different concrete proportions, coarse 6/12 (DC) diabase and coarse 6/12 (SC) slag have been used, limiting their quantities to avoid problems of blockage and segregation. Diabase sand 0/6 (DS), electric arc furnace slag 0/6 (SLS), and silica sand 0/2 (SIS) have been used as fine aggregates. The SCM used include limestone filler (LF), fly ash (FA), and cupola slag filler (CS). The granulometric distribution of the aggregates used (coarse and fine) according to EN 933-1 is shown in Figure 1.  
The physical-mechanical properties of the aggregates have been determined by characterizing the bulk specific gravity and porosity according to EN 1097-3, the apparent specific gravity and water absorption according to EN 1097-6, the resistance to fragmentation determining Los Angeles coefficient according to EN 1097-2 and the aggregates crushing value according to UNE 83112. The fine aggregates (cement and SCM) have been characterized by determining the actual density according to UNE 80103 and by the specific Blaine surface according to EN 196-6. The results obtained are shown in Tables 1 and 2. Both types of aggregates have excellent mechanical properties and a 35% higher density in the case of EAFS. The chemical characterization of the slags used was carried out by means of X-ray fluorescence (XRF), in order to determine the semi-quantitative concentration of compounds in oxides represented by percentages (Table 3). For this characterization an ARL-ADVANT-XP Thermo-spectrometer was used. It was observed that the main components of slags were iron, calcium, and silicon oxides, although there were traces of chromium and titanium oxides, probably generated during the injection of oxygen. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Material**} & **Bulk** & **Apparent** & & & & & \\  & **Specific** & **Specific** & **Absorption** & **Open** & **Loss Angeles** & **Aggregates** \\  & **Gravity** & **Gravity** & **[vol.\%]** & **[wt.\%]** & **[wt.\%]** & **[\%]** & **Cushing** \\  & **[g/cm\({}^{3}\)]** & **[g/cm\({}^{3}\)]** & & & & \\ \hline EAFS coarse & 3.65 & 3.85 & 1.43 & 5.22 & 15 & 18 \\ Diabase coarse & 2.72 & 2.81 & 1.11 & 3.02 & 15 & 15 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Main properties of the coarse aggregates used in the self-compacting concrete (SCC). Figure 1: Aggregates granulometric grading. On the other hand, the cupola slag shows high concentrations of silicon, calcium, and aluminum oxides, the first being an indicator of the possible reactivity of the material, since it is in an amorphous state. The compositions of the rest of the materials were obtained by Energy-dispersive X-ray spectroscopy (EDX) using a Zeiss EVO MA15 scanning electron microscope (SEM) equipped with an Oxford Instruments X-ray detector, selecting different representative areas of particles chosen randomly. The expansiveness of the EAFS is one of its main problems, and can cause cracking of concrete in the medium/long term. To avoid this phenomenon, EAFS aggregates have been submerged in pools for 24 h and have remained wet in storage stacks for 3 months, in order to hydrate free lime and magnesia. The expansiveness of the aggregates was determined according to EN 1744-1, obtaining values of 0.16 vol.% at 24 h and 0.17% vol. at 168 h, the first value being those required when the MgO content is less than 5%. The mortar proportions (Table 4) were carried out with CEM 152.5 R, CEN standardized sand and in accordance with the amounts proposed by EN 196-1 (except the amount of sand, slightly higher). The mortars were cured submerged in water at a temperature of \(20\pm 1\)\({}^{\circ}\)C. The manufacture of these mortars (M) was carried out using replacements of 0, 10, 20, 30 vol.% of cement by cupola slag filler, in order to establish the pozzolanity of the cupola slag compared to cement.