## 5 The Result Analysis
### Results and Discussion  
1. From the results in Table 9, we can see that the CO\({}_{2}\) emission fee of tunnel material is 467,445,245 won, and the CO\({}_{2}\) emission fee of main equipment is 21,832,991 won. The tunnel material takes over 95.32% of the total CO\({}_{2}\) emission fee; in order to reduce the tunnel CO\({}_{2}\) emission cost, the researchers should focus on the development of low carbon materials.
2. For the tunnel material, the CO\({}_{2}\) emission fee of cement treated base, concrete lining, drainage way and concrete slab (30 cm) is very high. Four of them take over 84.9% of the tunnel material CO\({}_{2}\) emission fee. Areas for further research would be to reduce the CO\({}_{2}\) emission factor of  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Category**} & \multirow{2}{*}{**Division**} & **10 m Section** & **Project A CO\({}_{2}\) Emission (kg)** & **Average Price of CO\({}_{2}\)** & **Annual** \\  & & **CO\({}_{2}\) Emission** & **emission (kg)** & **Average** \\  & & **(kg)** & **(1477.6 m)** & **(eur/kg)** & **Rate** \\ \hline \multirow{7}{*}{Tunnel material} & Drainage way & 7978.07 & 1,178,840 & & 38,063,956 \\  & Cement treated base & 37,226.64 & 550,060.8 & & 177,564,363 \\  & Common thick cover & 240 & 35,462.4 & & 1,144,757 \\  & Ditch cover & 5103 & 754,019.3 & & 24,340,390 \\  & Concrete lining & 26,298.03 & 3,885,797 & & 125,436,863 \\  & Drainage pipe filling & 85.15 & 12,581.76 & & 406,150 \\  & Drainage & 294.99 & 45,857.72 & & 1,407,049 \\  & Rock bolt & 3684.49 & 544,420.2 & 0.02472 & 1305.86 & 17,574,353 \\  & Shoterchete & 3960.21 & 585,160.6 & & 18,898,488 \\  & Steel pipe & 266.29 & 39,347.01 & & 1,270,155 \\  & Waterproofing sheet & 501.46 & 74,095.73 & & 2,391,874 \\  & Concrete slab (30 cm) & 7784.96 & 1,150,306 & & 37,132,856 \\ \hline \multirow{2}{*}{Main equipment} & Dump truck & 3709.86 & 585,169 & & 17,693,364 \\  & Mixer-truck & 638.14 & 94,291.6 & & 3,043,813 \\ \cline{1-1}  & Wheel loader & 229.32 & 33,884.3 & & 1,093,815 \\ \hline \hline \end{tabular}
\end{table}
Table 8: Calculation process of CO\({}_{2}\) emission fee during tunnel construction process for Project A.  
\begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Category**} & \multirow{2}{*}{**Division**} & **CO\({}_{2}\) Emission Fe** & **Total Fee (Won)** \\  & & **(Won)** \\ \hline \multirow{7}{*}{Tunnel material} & Drainage way & 38,053,956 & \\  & Cement treated base & 177,564,363 & \\  & Common ditch cover & 1,144,757 & \\  & Ditch cover & 24,340,390 & \\  & Concrete lining & 125,436,863 & \\  & Drainage pipe filling & 406,150 & 445,612,254 \\  & Drainpipe & 1,407,049 & (95.32\%) \\  & Rock bolt & 17,574,353 & \\  & Shoterchete & 18,889,488 & \\  & Steel pipe & 1,270,155 & \\  & Waterproofing sheet & 2,391,874 & \\  & Concrete slab (30 cm) & 37,132,856 & \\ \hline \multirow{2}{*}{Main equipment} & Dump truck & 17,695,364 & 21,832,991 \\  & Mixer-truck & 3,043,813 & (4.67\%) \\ \cline{1-1}  & Wheel loader & 1,093,815 & \\ \hline \hline \end{tabular}
\end{table}
Table 9: Proportion of CO\({}_{2}\) emission fee during the construction process of project A.  
cement and concrete, for example, by developing new types of cement and concrete, or using a replacement with lower CO2 emission factor.
3. Even though, compared with the tunnel material, the CO2 emission fee of the main equipment is not very high, it is a large expense for the whole tunnel project. According to the results, we can see that most of the CO2 emission fee comes from the dump truck. During the tunnel construction, the quantity of earthwork is very high, so there is more use of the dump truck. As a consequence, we should take the reduction of earthwork as an important consideration in the tunnel design. We can also design a reasonable construction route to reduce the transportation distance and improve the equipment, to reduce the fuel consumption of the dump truck.