## 3 Results and Discussion
### CO\({}_{2}\) Emissions Calculation  
CO\({}_{2}\) is the main greenhouse gas that causes global warming, and reducing carbon emissions is one of the world's most pressing issues today. Cement production results in significant CO\({}_{2}\) emissions, and using SCMs can reduce CO\({}_{2}\) emissions. Therefore, this study calculated and analyzed the CO\({}_{2}\) emissions and energy consumption for producing one cubic meter of mortar. The calculation only considered the CO\({}_{2}\) emissions under the mix ratio in this experiment, ignoring the CO\({}_{2}\) emissions generated during transportation and mixing. Table 7 shows the material mass required to produce one cubic meter of experimental mortar, Table 8 shows the carbon footprint and energy consumption per unit  
Figure 12: SEM image at 28 d. (**a**) 20 QZ, (**b**) C100, (**c**) 20 FA, (**d**) 20 FA, (**e**) FA. mass of raw materials used in this experiment [6; 23; 56], and Table 9 shows the calculation results of carbon emissions and energy consumption. Equation (5) limits the total volume of each concrete component (OPC, FA, QZ, sand, water) to 1 m\({}^{3}\)[57]:  
\[\sum_{i=1}^{n}\frac{m_{i}}{\rho_{i}}=1 \tag{7}\]  
where \(\rho_{i}\) represents the raw material density, \(m_{i}\) is the raw material unit volume density (kg/m\({}^{3}\)), n = 5, and i represents each component in the raw material mixture (OPC, FA, QZ, sand, water). According to Equations (8) and (9):  
\[\text{CO}_{2}\text{P}=\sum_{1}^{n}\text{CO}_{2}m_{i} \tag{8}\]  
\[\text{MJP}=\sum_{1}^{n}\text{MJ}m_{i} \tag{9}\]  
The CO\({}_{2}\) emissions and energy consumption per unit volume were calculated, where \"CO\({}_{2}\)P\" is the CO\({}_{2}\) emissions per cubic meter of mortar and mi is the mass of each raw material per unit mass (tons) of mortar mix. \"CO\({}_{2}\)\" is the CO\({}_{2}\) emission factor of the raw material (CO\({}_{2}\)kg/kg). \"MJP\" is the energy consumption of one cubic meter of mortar, and \"MJ\" is the energy release factor of the raw material (MJ/kg). The results in Table 9 show that with the addition of SCMs, the CO\({}_{2}\) emissions and energy consumption per unit volume of mortar have decreased significantly. The 20 FA group had the most significant reduction in carbon emissions and energy consumption, 17.47% and 13.58%, respectively. In actual engineering applications, while considering the reduction in CO\({}_{2}\) emissions, we should also consider the changes in cement mix proportions and the changes in cement product strength that will result. According to Equation (8) [6], the 28-day compressive strength of each group of sample mortar is normalized to CO\({}_{2}\) emissions: \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **Group** & **OPC (kg)** & **FA (kg)** & **QZ (kg)** & **Sand (kg)** & **Water (kg)** \\ \hline \multirow{6}{*}{Mortar} & C100 & 618.25 & 0 & 0 & 1236.50 & 309.12 \\  & 10 FA & 553.86 & 61.54 & 0 & 1230.82 & 307.70 \\  & 20 FA & 490.07 & 122.52 & 0 & 1225.19 & 306.30 \\  & 10 QZ & 554.37 & 0 & 61.60 & 1231.94 & 307.99 \\  & 20 QZ & 490.97 & 0 & 122.74 & 1227.42 & 306.85 \\  & 10 FA10 QZ & 490.52 & 61.31 & 61.31 & 1226.30 & 306.57 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: The quality of each raw material in one cubic meter. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Raw Materials** & **OPC** & **FA** & **QZ** & **Sand** & **Water** \\ \hline GWP (CO\({}_{2}\)kg/kg) & 0.86 & 0 & 0.023 & 0.01 & 0 \\ Energy emission (MJ/kg) & 2.451 & 0 & 0.820 & 0.539 & 0.20 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Carbon footprint and energy emission of raw materials used in this investigation. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Group** & **C100** & **10 FA** & **20 FA** & **10 QZ** & **20 QZ** & **10 QZ10 FA** \\ \hline CO\({}_{2}\) (kg) & 525.51 & 488.63 & 433.71 & 490.49 & 437.38 & 435.52 \\ Energy consumption (MJ) & 2243.63 & 2082.46 & 1938.97 & 2134.89 & 2026.96 & 1974.83 \\ \hline \hline \end{tabular}
\end{table}