## 2 Materials and Methods
### Materials

Table caption: a: Guanyinyan hydropower station; b: Suofengying hydropower station; c: Saige hydropower station; d: Guangzhou hydropower station; e: Fengman hydropower station reconstruction project; f: Shuangfengsi hydropower station; g: Shankouyan hydropower station; h: Ahai hydropower station; i: the stage III cofferdam of three gorges project; j: Kalasuke hydropower station; k: Kala hydropower station; i: Shatu hydropower station; m: jingangsham hydropower station; n: A report named \"Application of limestone flour and fly ash admixture in roller compacted concrete in cold area\"; o: A report named \"Application of natural volcanic ash as admixture in hydraulic concrete\"; p: A report named \"Effects of activity and content fluctuation of marble sand powder on concrete performance\"; q: The fifth international conference on roller compacted concrete dams; r: Guandi hydropower station. Kinds of concrete, RCC2: two-graded roller compacted concrete; RCC3: three-graded roller compacted concrete; OC2: two-graded ordinary concrete; OC3: three-graded ordinary concrete; OC4: four-graded ordinary concrete; CM: cement mortar. The basic information of the adopted two applications in practical engineering are briefed herein. The Fengman hydropower station reconstruction project is the largest dam in northeast China. The mix proportion of three-graded roller compacted concrete in Fengman is listed in Table 2. The water-binder ratio is 0.5; and the dosage of fly ash varies from 45% total cementitious material to 65% total cementitious material by weight. Accordingly, the compressive strength of three-graded roller compacted concrete is shown in Table 3.  
Slag is very abundant in southwest China, and a large amount of slag is piled up in the open air resulting in environmental pollution. Therefore, it is necessary to study the concrete in Suofengying, which mixed with slag. The mix proportions of three-graded roller compacted concrete in Suofengying is shown in Table 4. The water-binder ratio is 0.55 and the dosage of supplementary cementitious material (slag and fly ash) varies from 20% of the total cementitious material to 60% of the total cementitious material by weight. Accordingly, the compressive strength of three-graded roller compacted concrete in Suofengying is shown in Table 5. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Group**} & \multicolumn{5}{c}{**Constitution (kg/m\({}^{3}\))**} \\ \cline{2-6}  & **Water** & **Cement** & **Fly Ash** & **Slag** & **Sand** & **Aggregate** \\ \hline
1 & 75 & 109 & 27 & 0 & 801 & 1488 \\
2 & 75 & 109 & 14 & 14 & 802 & 1489 \\
3 & 81 & 118 & 0 & 29 & 818 & 1454 \\
4 & 75 & 96 & 41 & 0 & 800 & 1485 \\
5 & 75 & 82 & 55 & 0 & 797 & 1481 \\
6 & 75 & 82 & 27 & 27 & 798 & 1482 \\
7 & 75 & 68 & 68 & 0 & 794 & 1477 \\
8 & 75 & 55 & 82 & 0 & 791 & 1473 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Mix proportions of the Suofengying three-graded roller compacted concrete. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Group**} & \multicolumn{5}{c}{**Constitution (kg/m\({}^{3}\))**} \\ \cline{2-6}  & **Water** & **Cement** & **Fly Ash** & **Sand** & **Aggregate** \\ \hline
1 & 86 & 94.6 & 77.4 & 658 & 1465 & 3.9 \\
2 & 86 & 77.4 & 94.6 & 655 & 1460 & 3.0 \\
3 & 86 & 60.2 & 111.8 & 653 & 1455 & 3.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Mix proportions of three-graded roller compacted concrete. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Group**} & \multicolumn{5}{c}{**Compressive Strength (MPa)**} \\ \cline{2-6}  & **7 days** & **28 days** & **90 days** \\ \hline
1 & / & 22.4 & 36.7 \\
2 & 9.7 & 21.2 & 35.1 \\
3 & / & 17.4 & 29.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Compressive strength of three-graded roller compacted concrete.