# Effect of Calined Marble Powder and Magnetized Water on the Performance of Cement-Based Composites
## 3 Results and Discussion
### Flexural Strength (\(f_{\text{fs}}\))  
Figure 7 presents the \(f_{\text{fs}}\) data of cementitious composites with RMP and CMP replacements after curing periods of 3, 7, and 28 days. The \(f_{\text{fs}}\) tests were conducted on three samples for each mixture, and the average values were calculated. As observed in Figure 7, the \(f_{\text{fs}}\) values increase with longer curing periods for each mixture group. Overall, the results indicate that RMP replacement reduces the \(f_{\text{fs}}\) values, while higher \(f_{\text{fs}}\) values are achieved with CMP replacement. Furthermore, when CMP  
Figure 7: The flexural strengths of the cementitious mortars for curing periods. replaced mortars are produced with MW, a more pronounced increase in _f\({}_{\rm{fs}}\)_ values are observed. The _f\({}_{\rm{fs}}\)_ values of the mortars coded as R_-/TW decrease with increasing RMP replacement ratios for the 3-, 7-, and 28-day curing periods. Figure 8 shows the percentage changes in _f\({}_{\rm{fs}}\)_ values of RMP- and CMP-replaced cementitious composites produced with TW and MW compared to the reference mortar at 3, 7, and 28 days. The _f\({}_{\rm{fs}}\)_ values of RMP-replaced mortars, compared to the reference mortar coded as RQ/TW, exhibit decreases of 1.1% to 27.7%, 8.0% to 27.6%, and 2.9% to 25.5% for the 3-, 7-, and 28-day curing periods, respectively. The _f\({}_{\rm{fs}}\)_ values of mortars coded as C\(\overline{\rm{5}}\)/TW show increases of 11.9%, 5.7%, and 4.3% compared to the reference mortar coded as C\(\overline{\rm{Q}}\)/TW for the 3-, 7-, and 28-day curing periods, respectively. When examining the percentage changes in _f\({}_{\rm{fs}}\)_ values of CMP-replaced mortars produced with TW in comparison to the reference mortar (Figure 8), it can generally be stated that the highest _f\({}_{\rm{fs}}\)_ values are obtained from mortars with a 5% CMP replacement. A similar trend in _f\({}_{\rm{fs}}\)_ values is observed for the mortars coded as C\(\overline{\rm{5}}\)/MW, where the 3-, 7-, and 28-day _f\({}_{\rm{fs}}\)_ values increase by 13.3%, 4.6%, and 3.6%, respectively, compared to the reference mortar coded as C\(\overline{\rm{Q}}\)/MW. When comparing the _f\({}_{\rm{fs}}\)_ values of mortars coded as C_-/TW with those coded as C_-/MW, it is observed that using MW as the mixing water leads to increases in the 3-, 7-, and 28-day _f\({}_{\rm{fs}}\)_ values by varying amounts, ranging between 7.2% to 12.5%, 5.6% to 9.1%, and  
Figure 8: Change in flexural strengths of the cementitious mortars for curing periods. 5.2% to 7.1%, respectively. Overall, the results from the \(f_{\text{fs}}\) tests indicate that CMP-replaced mortars exhibit higher ffs values compared to RMP-replaced mortars. [PERSON] et al. [5] reported that, when RMP is used as a cement substitute, the reduction in mechanical properties can be attributed to the lower content of primary compounds such as C3S and C2S, which are essential for hydration and strength development. Furthermore, it was noted that RMP primarily consists of non-reactive calcite and dolomite. Replacing cement with these less reactive materials reduces the formation of hydration products, which are vital for forming a stable and interconnected microstructure. As a result, RMP contributes to a weak and porous microstructure in the cement paste, leading to lower mechanical strength. The observed decreases in flexural strengths with increasing RMP replacement ratios are consistent with findings in the literature [44]. In contrast, when CMP is used in cement pastes, an increase in \(f_{\text{fs}}\) values is noted compared to those produced with RMP. During the calcination of RMP, dolomite and calcite phases decompose at high temperatures, resulting in the formation of free CaO and MgO. Free CaO contributes to the hydration process of the cement paste. The dense microstructure resulting from the formation of hydration products enhances the mechanical properties of cementitious composites [5].