## 3 Results and Discussions
### Characterization of Raw Materials
Subsequently, after determining the chemical composition of the electric arc furnace slag, the physical properties of the slag proceeded to evaluate. The electric arc furnace slag performs the function of a coarse and fine aggregate in the bituminous mixture, which is why the tests carried out are those detailed in Table 9.  
Figure 5: Results of X-ray diffraction of electric arc furnace slag. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Compound** & **Wt, \%** & **Est. Error** \\ \hline CaO & 31.75 & 0.23 \\ Fe\({}_{2}\)O\({}_{3}\) & 21.96 & 0.21 \\ SiO\({}_{2}\) & 17.52 & 0.19 \\ Al\({}_{2}\)O\({}_{3}\) & 12.26 & 0.16 \\ MnO & 6.15 & 0.12 \\ MgO & 5.05 & 0.11 \\ Cr\({}_{2}\)O\({}_{3}\) & 2.73 & 0.08 \\ TiO\({}_{2}\) & 0.955 & 0.047 \\ BaO & 0.658 & 0.033 \\ P\({}_{2}\)O\({}_{5}\) & 0.319 & 0.016 \\ SrO & 0.186 & 0.0093 \\ V\({}_{2}\)O\({}_{5}\) & 0.159 & 0.0079 \\ Nb\({}_{2}\)O\({}_{5}\) & 0.0659 & 0.0033 \\ S & 0.0645 & 0.0032 \\ ZrO\({}_{2}\) & 0.0551 & 0.0028 \\ K\({}_{2}\)O & 0.0289 & 0.0016 \\ CuO & 0.0254 & 0.0017 \\ ZnO & 0.0245 & 0.0016 \\ Co\({}_{3}\)O\({}_{4}\) & 0.0147 & 0.0016 \\ Eu\({}_{2}\)O\({}_{3}\) & 0.0137 & 0.0065 \\ WO\({}_{3}\) & 0.0104 & 0.0031 \\ Y\({}_{2}\)O\({}_{3}\) & 0.0018 & 0.0005 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: X-ray fluorescence of electric arc furnace slag. Physical testing of the electric arc furnace slag showed that the density of the particles was higher than that of a conventional aggregate, considering as the norm that the density of a conventional aggregate is 2650 kg/m\({}^{3}\). This fact, although it is not a problem, must be taken into account for the proportioning of the materials, so that volumetric corrections are necessary. If these corrections were not made, the properties of the final material could be damaged. At the same time, the sand equivalent test reflected the low proportion of colloidal particles, not producing subsequent problems of expansiveness. It is worth noting the excellent results obtained in the broken surfaces and flakiness index tests. These results reflect the singular shape of the electric arc furnace slag particles, with a multitude of sharp edges and similar dimensions in all three axes. They are therefore ideal for use in bituminous mixtures with discontinuous grading where the compressive loads of traffic are supported by internal friction of the particles. At the same time, it should be noted that bituminous mixtures with discontinuous grading have a series of advantages over mixtures with continuous grading, mainly a higher void content. However, this discontinuous grading makes it necessary for the coarse aggregate to be of high quality, since it is the main responsible for supporting the compressive loads of traffic. Therefore, the coarse aggregate must have adequate shape and mechanical characteristics. The shape characteristics of the particles of the electric arc furnace slag have already been defined previously, so it is necessary to corroborate the mechanical resistance. This mechanical resistance has been evaluated through the test of resistance to fragmentation and resistance to freezing-thawing cycles, reflecting values of 13 \(\pm\) 1% and 0.551 \(\pm\) 0.016% respectively. At the same time, it is essential that the aggregates provide an adequate macrotexture and microtexture for a correct friction between the tire and the pavement. This property is evaluated with the determination test of the polished stone. This test reflected a value of 58 \(\pm\) 1, demonstrating the correct resistance in time of the aggregates and ensuring the roughness of the pavement during its working life. Finally, and to corroborate that high concentrations of chemical pollutants are not leached, the leachates from the electric arc furnace and ladle furnace slag were analyzed in accordance with the UNE-EN 12457-3 standard.