## 2 Experimental Program  
The selected experimental parameters are listed in Table 1. The largest category is cement-based materials, and the three types of cement-based materials were cement paste made of water and cement; mortar made of water, cement, and sand; and concrete made of water, cement, and fine aggregates. The selected MWCNT concentrations were 0.125, 0.25, and 0.5 wt% with respect to the cement weight, respectively, and the curing periods were 7 and 28 d.  
Figure 1 shows the nomenclature of the composites. The first part of the specimen name indicates the cement-based material type. \"CP\" represents cement paste made of water and cement, \"M\" represents mortar made of water, cement, and sand of 1 mm or smaller in diameter, and \"Co\" represents concrete made of water, cement, and fine aggregates of 3 mm or larger in diameter. The second part indicates the MWCNT concentration with respect to the cement weight, i.e., \"0.125,\" \"0.25,\" and \"0.5.\" The third part indicates the number of curing days, i.e., \"7D\" for 7 days and \"28D\" for 28 days. The last part indicates the presence of damage, for which \"X\" represents no damage and \"O\" indicates that damage has occurred. \begin{table}
\begin{tabular}{c c c c} \hline
**Specimen Name** & **Composite Type** & **Curing Days** & **Concentration (wt\%)** \\ \hline CP-0.125-7D-X & & & 0.125 \\ CP-0.125-7D-O & & & 0.125 \\ CP-0.25-7D-X & & 7 & 0.25 \\ CP-0.5-7D-X & & & 0.5 \\ CP-0.5-7D-O & Cement paste & & 0.125 \\ CP-0.125-28D-X & & & 0.25 \\ CP-0.125-28D-O & & 28 & 0.25 \\ CP-0.5-28D-X & & & 0.5 \\ CP-0.5-28D-O & & & 0.5 \\ \hline M-0.125-7D-X & & & 0.125 \\ M-0.125-7D-O & & & 0.25 \\ M-0.25-7D-X & & 7 & 0.25 \\ M-0.5-7D-X & & & 0.5 \\ M-0.5-7D-O & & & 0.5 \\ M-0.125-28D-X & & & 0.125 \\ M-0.25-28D-O & & & 0.25 \\ M-0.25-28D-X & & 28 & 0.25 \\ M-0.5-28D-X & & & 0.5 \\ M-0.5-28D-O & & & 0.5 \\ \hline Co-0.125-7D-X & & & 0.125 \\ Co-0.125-7D-O & & & 0.125 \\ Co-0.25-7D-X & & & 0.25 \\ Co-0.5-7D-O & & & 0.5 \\ Co-0.125-28D-X & Concrete & & 0.125 \\ Co-0.125-28D-O & & & 0.25 \\ Co-0.25-28D-O & & 28 & 0.25 \\ Co-0.5-28D-X & & & 0.5 \\ \hline \end{tabular}
\end{table} 
Table 1: Parameters of cement composite temperature tests. Figure 1: Specim name. coefficient of 1.0-1.93. Ordinary Portland cement of American Society for Testing Materials Type I was used for all the composites [28; 29]. MWCNTs with a purity of 99%, a diameter of 0.5-1.0 nm, a length of 100 nm to 1 cm, and in a functionalized aqueous solution state were used [30; 31; 32]. The MWCNT solution was dispersed using 22 kHz ultrasonic waves in a polyacrylic acid copolymer for 2 h [13; 33]. The properties of the MWCNTs used in this study are listed in Table 2. The sand-cement weight ratio of the composites was set to 1:2.5, and the water-cement ratio was set to 50%. The cement paste was fabricated with 140 g of a MWCNT solution and 280 g of sand. The mortar was fabricated with 40 g of a MWCNT solution, 80 g of cement, and 200 g of sand. Finally, the concrete was fabricated with 40 g of a MWCNT solution, 80 g of cement, and 200 g of sand mixed with fine aggregates. Figure 3 shows the fabrication process of the composites. The sand, cement, and MWCNT solutions used in the composites were weighed according to the mixing ratio (Figure 3a). The weighed sand and cement were dry mixed for 2 min to achieve a uniform material (Figure 3b). The MWCNTs dispersed in the solution were mixed with the dry-mixed sand and cement for 3 min (Figure 3c). The mixed paste was placed in two layers in the mold and compacted approximately 30 times for each layer (Figure 3d). For the composites with damage, a piece of Styrofoam (10 \(\times\) 10 \(\times\) 20 mm) was placed at the center before placing and compacting the paste. After compaction, stainless-steel meshes of 50 \(\times\) 30 mm were placed at 2.5-cm intervals in the composites for applying the voltage (Figure 3e). In addition, a thermocouple was inserted at a depth of 1 cm to measure the temperature inside the composites (Figure 3f).