# Physical-Mechanical Properties of Cupola Slag Cement Paste
## 2 Materials and Methods
### Methods
#### 2.2.2 Mortar Manufacture, Curing Conditions and Testing Procedure  
The manufacturing process of the mortars was as defined by EN-196-1 [39], see Figure 2(a). Twenty-four hours after the mortars were manufactured, they were demoulded and placed in a humidity chamber for curing, Figure 2(b). \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & **M-Rf** & **M-20-A** & **M-20-B** & **M-20-C** & **M-50-A** & **M-50-B** & **M-50-C** & **M-50-D** \\ \hline CEM III-32.5N [g] & 317.5 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ CEM I-52.5R [g] & 0 & 253.2 & 252.4 & 251.6 & 158.2 & 157.7 & 157.2 & 156.7 \\ Cupola slag (CSF) [g] & 0 & 63.3 & 63.1 & 62.9 & 158.2 & 157.7 & 157.2 & 156.7 \\ Sand [g] & 571.4 & 569.6 & 567.8 & 566.0 & 569.6 & 567.8 & 566 & 564.3 \\ Water [g] & 111.1 & 113.9 & 116.7 & 119.5 & 113.9 & 116.7 & 119.5 & 122.3 \\ \hline Fine particles [g] & 317.5 & 316.5 & 315.5 & 314.5 & 316.5 & 315.5 & 314.5 & 313.5 \\ Sand/cement & 1.8 & 1.8 & 1.8 & 1.8 & 1.8 & 1.8 & 1.8 & 1.8 \\ Water/Cement & 0.35 & 0.36 & 0.37 & 0.38 & 0.36 & 0.37 & 0.38 & 0.39 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Mortar mix proportions. Figure 3: Mortar manufacture (**a**). Mortar specimens (**b**). For the determination of the consistency of the mortars, the procedure according to EN 1015-3--Methods of test for mortar for masonry--Part 3: Determination of consistency of fresh mortar (by flow table) [40] is followed. Very similar to that used to determine the consistency of concrete by means of a shaking table. In the case of concrete [41], there is a limitation regarding the maximum size of the aggregate of 64 mm. In the case of mortar, the limitation is 4 mm. In both tests, the fresh cone is shaken 15 times to finally measure the diameter in two perpendicular directions. Figure 4 shows an example of the parameters registered in each test (d1 and d2). The compressive strength was determined according to EN 196-1 [39] (prismatic specimens of 160 \(\times\) 40 \(\times\) 40 mm and at a loading rate of 50 Nm/s). An example of the compressive strength test set-up is shown in Figure 5.  
Figure 4: Mortar workability test measurement process. Figure 5: Mechanical tests, compressive strength. An example of the results of the chemical composition analysis performed on cupola slag samples restricted to its elemental components is shown in Figure 7 and Table 4 below. The casting process is a highly complex process involving a large number of variables. For this reason, slight variations in the chemical composition of cupola slag are expected. Therefore, a study of the evolution of the different components present in the cupola slag over time was carried out. To make this analysis easier, these components were divided into two groups according to the quantity present in each of them: main components and secondary components, see Figure 8. In this figure, the Y-axes indicate the quantity of each component, see legend. For the X-axis, this is a linear scale of the time indicated at the bottom of the figure. The graphs above show the evolution, over time, of the components present in the cupola slag that can be used to replace cement. The left graphs show the evolution of in time of CaO, SiO\({}_{2}\), Al\({}_{2}\)O\({}_{3}\), MgO and Fe\({}_{2}\)O\({}_{3}\), while the right graphs show the evolution in time of K\({}_{2}\)O, P\({}_{2}\)O\({}_{5}\), MnO, SO\({}_{3}\), Cr\({}_{2}\)O\({}_{3}\) and TiO\({}_{2}\). In the case of the principal components, it can be seen that Al\({}_{2}\)O\({}_{3}\) remains practically constant, with values between 10 and 15% by weight, as well as MgO and Fe\({}_{2}\)O\({}_{3}\), whose values over time are around 5% by weight, with some peaks. CaO and SiO\({}_{2}\) show somewhat more variability, but within acceptable limits. The greatest variability is observed in the secondary components, but their effect is minor for our purposes. In case of the secondary components, it can be seen that except MnO and specially SO\({}_{3}\) the other components are quite stable on time.