## 3 A Simulation Model and Verification of Its Rationality
### A Typical Over-Track Building Model and Its Parameter Setting  
To investigate the influence of train vibration on over-track buildings in the throat area of metro depot under different building parameters, an over-track building was set up based on the model of an over-track platform of a metro depot, as shown in Figure 3. The parameters of the over-track platform and the over-track building are shown in Tables 4 and 5, respectively. The height of each storey is \(3.0\) m, and the thickness of each floor is \(0.12\) m. The cross-sectional dimensions of columns and beams in the frame structure building are \(0.5\) m \(\times\)\(0.5\) m and \(0.3\) m \(\times\)\(0.6\) m, respectively. The thickness of an infill wall is \(0.2\) m, and the thickness of a load-bearing wall in a shear-wall building is \(0.2\) m. The effects of a single factor change on indoor vibration in over-track buildings were analysed, and corresponding results are shown in Tables 4 and 5. Figure 8: The measured results of vertical vibration at C1: (**a**) vibration acceleration in time domain; (**b**) frequency spectra of vibration acceleration between \(0\) Hz and \(250\) Hz. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Measurement Point**} & \multicolumn{4}{c}{\(\textbf{V}\textbf{L}_{\textbf{Z}\textbf{max}}\) (dB)} & \multicolumn{4}{c}{_VAL (dB)_} \\ \cline{2-10}  & **Measured Results** & **Simulated Results** & **Error** & **Relative Error** & **Measured Result** & **Simulated Result** & **Error** & **Relative Error** \\ \hline C2 & \(83.9\) & \(85.1\) & \(1.2\) & \(1.43\%\) & \(100.7\) & \(102.1\) & \(1.4\) & \(1.39\%\) \\ C3 & \(82.3\) & \(83.1\) & \(0.8\) & \(0.97\%\) & \(94.1\) & \(95.2\) & \(1.1\) & \(1.17\%\) \\ C4 & \(81.8\) & \(82.0\) & \(0.2\) & \(-0.24\%\) & \(90.4\) & \(91.0\) & \(0.6\) & \(0.66\%\) \\ C5 & \(80.6\) & \(80.2\) & \(-0.4\) & \(-0.50\%\) & \(86.5\) & \(86.1\) & \(-0.4\) & \(-0.46\%\) \\ C6 & \(79.9\) & \(79.3\) & \(-0.6\) & \(-0.75\%\) & \(84.4\) & \(84.0\) & \(-0.4\) & \(-0.47\%\) \\ C7 & \(79.3\) & \(77.8\) & \(-1.5\) & \(-1.89\%\) & \(83.6\) & \(82.7\) & \(-0.9\) & \(-1.08\%\) \\ C8 & \(78.7\) & \(78.2\) & \(-0.5\) & \(-0.64\%\) & \(82.4\) & \(81.8\) & \(-0.6\) & \(-0.73\%\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: The comparison between the measured results and simulated results in a civil building. The Influence of the Total Amount of Storeys and Type of Building Structure on Indoor Vibration Caused by a Train  
The \(VL_{\text{Zmax}}\) of each storey in frame and shear wall structure buildings was shown in Figure 9. When the total amount of storeys (\(N\)) in buildings was the same, the \(VL_{\text{Zmax}}\) in frame buildings would be approximately 1.4-6.0 dB higher than that in shear wall structures. The \(VL_{\text{Zmax}}\) fluctuated, approximately rose with the increase in \(N\), and reached the maximal value at the top storey. Compared with that of the first storey, the \(VL_{\text{Zmax}}\) of the top storey was amplified by approximately 3.8-11.1 dB. Similarly, [PERSON] [21] carried out a vibration simulation and found that the floor vibration in buildings decreased initially and then increased with the increase in storeys. [PERSON] [22] measured the vibration of over-track buildings of metro depots, which indicated that the floor vibration oscillated with the increase in storeys. Vibrations on upper storeys in building were slightly amplified. The floor vibration of the second storey was significantly higher than that of the first storey. The main reason is that the first floor of the building is connected to the over-track platform and as such the vibration of the first floor is limited. The linear fitting results between \(N\) and the \(VL_{\text{Zmax}}\) of the first floor in frame and shear wall structures are shown in Figure 10. They show that the \(VL_{\text{Zmax}}\) of the first floor would decrease by approximately 0.20-0.47 dB when \(N\) increases by 1.