## 2 Materials and Methods
### Main Research
#### 3.2.3 Freeze-Thaw Resistance Tests  
The test results are summarized in Table 12, which shows the weight and strength losses of the specimens depending on the number of freezing and thawing cycles. In Figure 5, the ordinate scale displays the freeze-thaw-resistance levels (according to the classification [22]) corresponding to each type of specimen on the abscissa scale. The  
Figure 4: Strength test results: (**a**) Compressive strength of modified and reference samples; (**b**) Bending strength of modified and reference samples; (**c**) Relative strength increase (%) in compression and bending compared to the reference sample; (**d**) Coefficient of variation (%) for compressive and bending strength. Note: values are presented as mean \(\pm\) standard deviation based on 8 samples. auxiliary ordinate scale presents the coefficients of variation in the datapoints relating to the freeze-thaw resistance levels. Figure 5a illustrates the freeze-thaw resistance levels for weight loss, while Figure 5b presents those for strength loss. According to the results of the tests, the data on the serviceability of SCC under conditions of cyclic freezing and thawing were obtained. According to the requirements [22], the maximum permissible weight loss is not more than 2%, and the strength loss is not more than 15%. The reference samples were the most susceptible to frost damage; the maximum life cycle, with respect to weight loss, did not exceed 300 cycles; when the weight loss was 2.12%. The life cycle with respect to strength loss did not exceed 350 cycles, at which point, the strength reduction was 18%. The maximum values of weight loss of those samples of two-component composition (Type 2-4) were achieved at 400 cycles, and were from 2.0 to 2.02%, and the maximum values of strength loss at 600 cycles reached a critical value of 15%. The best results were shown by samples with a three-component composition (Type 5-7), where the maximum weight loss observed at 500 cycles ranged from 2.63 to 2.66%. The loss of strength of samples of Type 5-7 did not reach the limit value even after 600 cycles of freezing and thawing (only 9-10%), which confirms the sufficient reserve of strength and freeze-thaw resistance of the SCC compositions with three-fraction binder,  
Figure 5: Freeze–thaw resistance levels of concrete series: (**a**) Based on weight loss; (**b**) Based on strength loss. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Types**} & \multicolumn{5}{c}{**Weight Loss, \%**} & \multicolumn{5}{c}{**Strength Loss \({}^{*}\), \%**} \\ \cline{2-13}  & **200** & **300** & **350** & **400** & **500** & **600** & **200** & **300** & **350** & **400** & **500** & **600** \\ \hline Type 1: Reference sample & 1.27 & 2.12 & 3.08 & 4.07 & - & - & 0.97 & 0.90 & 0.82 & 0.71 & - & - \\ Type 2: 0/80/20 & 0.66 & 1.42 & 1.69 & 2.02 & 3.42 & 5.03 & 0.99 & 0.97 & 0.96 & 0.94 & 0.87 & 0.84 \\ Type 3: 0/75/25 & 0.62 & 1.41 & 1.67 & 2.01 & 3.11 & 4.79 & 0.99 & 0.98 & 0.97 & 0.95 & 0.87 & 0.85 \\ Type 4: 0/70/30 & 0.63 & 1.40 & 1.68 & 2.00 & 3.07 & 4.89 & 1.00 & 1.00 & 0.98 & 0.96 & 0.93 & 0.87 \\ Type 5: 15/80/5 & 0.41 & 0.96 & 1.32 & 1.86 & 2.63 & 3.17 & 1.00 & 1.00 & 1.00 & 0.95 & 0.93 & 0.90 \\ Type 6: 15/75/10 & 0.42 & 0.97 & 1.34 & 1.89 & 2.66 & 3.22 & 1.00 & 1.00 & 1.00 & 0.97 & 0.95 & 0.91 \\ Type 7: 15/70/15 & 0.42 & 0.98 & 1.35 & 1.91 & 2.67 & 3.25 & 1.00 & 1.00 & 1.00 & 0.98 & 0.96 & 0.91 \\ \hline \hline \end{tabular} \({}^{*}\)The ratio of the strength of a sample after testing to its strength before testing.  
\end{table} 
Table 12: Freeze–thaw resistance: weight and strength loss over cycles. and also shows the positive role of additional clinker stock in cement stone (stock of coarse particles--fraction 1500 cm\({}^{2}\)/g) contributing to the durability of concrete, by self-healing the defects in the structure [32].