# Carbon Emission Analysis of RC Core Wall-Steel Frame Structures
## 3 Results
### Results of Carbon Emission Analysis  
Based on the detailed building information, a BIM model is constructed in Revit, as depicted in Figure 3. Additionally, Chenxi Quantity Calculation software is utilized to generate the material list and quantities. Combined with the CEF database, the carbon emissions during the material production stage can be calculated, as listed in Table 2.  
According to Table 2, the total carbon emissions during the material production stage amount to 13,214.531 tCO\({}_{2}\)e. Figure 4 shows the carbon emission shares for each category of main materials during the production stage. The results illustrate that steel and concrete account for the largest shares, at 67.61% and 29.29%, respectively, during the production stage. In contrast, the carbon emissions from gypsum, wood, coatings, and membranes are relatively low, each contributing less than 1%. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Material** & \multirow{2}{*}{**Material Name**} & \multirow{2}{*}{**Unit**} & \multirow{2}{*}{**Amount**} & \multirow{2}{*}{**Carbon Emission**} \\
**Category** & & & & **(tCO\({}_{2}\)e)** \\ \hline \multirow{4}{*}{Steel} & Large-scale steel & t & 445.12 & 1059.386 \\  & Medium and small-scale steel & t & 2066.83 & 4857.050 \\  & Steel bar & t & 1289.6233 & 3017.719 \\ \hline \multirow{4}{*}{Concrete} & C25 concrete & m\({}^{3}\) & 279.871 & 79.763 \\  & C30 concrete & m\({}^{3}\) & 4138.175 & 1220.761 \\ \cline{1-1}  & C40 concrete & m\({}^{3}\) & 1280.100 & 411.424 \\ \cline{1-1}  & C50 concrete & m\({}^{3}\) & 1564.172 & 602.206 \\ \cline{1-1}  & C60 concrete & m\({}^{3}\) & 3732.958 & 1555.748 \\ \hline Gypsum & Waterproof putty for plastering & m\({}^{2}\) & 74.89 & 34.300 \\ \hline Wood & Wood & m\({}^{3}\) & 8.218 & 1.463 \\ \hline \multirow{4}{*}{Glass, doors, windows, etc.} & Flat glass & t & 188.4 & 212.892 \\  & Aluminum alloy window & m\({}^{2}\) & 4.16 & 1.056 \\ \cline{1-1}  & Light steel joists & t & 62.8 & 9.371 \\ \cline{1-1}  & Fire doors & m\({}^{2}\) & 1158.45 & 144.806 \\ \hline \multirow{4}{*}{Coatings and membranes} & Modified asphalt waterproofing & \multirow{2}{*}{m\({}^{2}\)} & \multirow{2}{*}{18,414.2} & \multirow{2}{*}{5.894} \\ \cline{1-1}  & membranes & & & \\ \cline{1-1}  & Epoxy resin paint for staircase treads & m\({}^{2}\) & 1017.6 & 0.692 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Carbon emissions for main materials during production stage. Figure 3: BIM model for super high-rise office building. The quality of the building materials during transportation is determined according to the quantities listed in Table 2. The transportation distances are based on the default values provided in [49] with concrete having a transportation distance of 40 km and other materials having a transportation distance of 500 km. Road transportation (gasoline) is utilized. The results are shown in Table 3.  
The total carbon emissions during the transportation stage is 358.587 tCO2e. As shown in Figure 5, the carbon emission shares during the transportation stage for various building materials are illustrated. It can be seen that steel and concrete have the highest carbon emission shares during the transportation stage, similar to the production stage. This indicates that these two types of building materials play a significant role in carbon emissions. Additionally, this reaffirms the rationale for primarily considering steel and concrete when evaluating the impact of building material types on carbon emissions. For the construction stage, the carbon emissions from energy consumption during the construction process can be estimated with Equation (5). Given that the office building has a total floor area of 31,400 m\({}^{2}\) with 21 floors, the carbon emissions for energy consumption during the construction process amount to 721.886 tCO2e. For the carbon emissions from formwork, the average turnover times are considered to be 4 times for wooden formwork and 35 times for both steel and aluminum formwork.