## 3 Results and Discussion
### Thermal Analysis  
Figures 15-18 show the results from thermogravimetric analyses of the modified cement pastes and plain cement paste. Generally, the TGA results show the common curves for hardened cement paste. In the TGA result of the cement pastes before 145 \({}^{\circ}\)C, the weight loss belongs to the free water included in each sample [39]. Therefore, for comparing the TGA results of three pastes, the point 100% weight should be put at 145 \({}^{\circ}\)C (see Figure 15). The thermal analysis result of the hardened cement paste sample normally consists of three processes, namely the dehydration of CSH, dehydration of CH, and decarbonation of calcite, which are related to three temperature ranges at 145 \({}^{\circ}\)C-200 \({}^{\circ}\)C, 400 \({}^{\circ}\)C-500 \({}^{\circ}\)C, and 550 \({}^{\circ}\)C-900 \({}^{\circ}\)C, respectively [11, 43, 44, 45]. Figure 15 shows that the weight loss from the thermal analysis of the hardened cement paste blended with CNT-TEOS/PVP NFs is the highest, followed by the hardened cement paste blended with TEOS/PVP NFs, while the lowest weight loss belonged to that of the plain paste. Figures 16-18 present the TGA/DTG results of each sample and the detail of the %weight loss that peaked out from the curves. The %weight loss of hydration products from the modified cement pastes is more than that of the plain pastes. Specifically, the amount of CSH phase in the pastes containing TEOS/PVP NFs and CNT-TEOS/PVP NFs is higher than that in the plain pastes. Our findings confirmed that the more compacted structure that developed inside the modified pastes was a result of the increased CSH content. Additionally, CSH is the primary component that formed the long-term strength and durability of cement-based materials [46], explaining the increase in compressive strength. In Figure 18, a peak around 550 \({}^{\circ}\)C to 650 \({}^{\circ}\)C is attributed to the weight loss of CNTs, which is found in [47]. Above all, the TGA results are suitable with the above results, namely that the higher proportion of hydrates in the cement matrix, which were blended with TEOS/PVP NFs and CNT-TEOS/PVP NFs, explained the increase in the compressive strength of cementitious materials. Figures 15-18 show the results from thermogravimetric analyses of the modified cement pastes and the plain cement paste. Generally, the TGA results show the common curves for hardened cement paste. As the authors' knowledge, in the TGA result of cement pastes, before 145 \({}^{\circ}\)C, the weight loss belongs to the free water included in each sample [39]. Therefore, for comparing the TGA results of three pastes, the point 100% weight should be put at 145 \({}^{\circ}\)C (see Figure 15). As reported from the literature, the thermal analysis result of hardened cement paste sample normally consists of three processes the dehydration of CSH, dehydration of CH, and the decarbonation of calcite, which is related to three temperature ranges at 145 \({}^{\circ}\)C-200 \({}^{\circ}\)C, 400 \({}^{\circ}\)C-500 \({}^{\circ}\)C, and 550 \({}^{\circ}\)C-900 \({}^{\circ}\)C, respectively [11, 43, 44, 45]. As can be seen from Figure 15, the weight loss from the thermal analysis of the hardened cement paste blended with CNT-TEOS/PVP NFs is the highest, followed by the observation of the hardened cement paste blended with TEOS/PVP NFs and the lowest weight loss has belonged to that of the plain paste. Figures 16-18 present the TGA/DTG results of each  
Figure 14: EDS results of cement paste containing CNT-TEOS/PVP NFs: (**a**) SEM image; (**b**) EDS spectrum—focus on nanofibers zone. sample and the detail of %weight loss that peaked out from the curves. It is clear that the %weight loss of hydration products from the modified cement pastes is more than that of the plain pastes. Especially the amount of CSH phase in the pastes containing TEOS/PVP NFs and CNT-TEOS/PVP NFs is higher than that in the plain pastes.