## 4 Analysis of Results
### Comparison of the Structural Horizontal Response  
Figure 21 shows the horizontal displacement-time curves between the upper and lower plates of the structure. The horizontal deformation was the largest of the three types of bearings after setting the ring spring bearing. The maximum horizontal relative displacement was 17.5 cm in the El Centro earthquake and 22.6 cm in the Kobe earthquake, which is smaller than the deformation in the original structure. However, the structure was still damaged, indicating that horizontal seismic isolation measures and vertical seismic isolation measures are essential for the underground structure. This shows that seismic isolation measures in both horizontal and vertical directions are essential for the underground structure, and seismic forces in both directions will cause great damage to the structure. The horizontal deformation of the structure was 10.6 cm in the El Centro earthquake and 9.5 cm \begin{table}
\begin{tabular}{c c c c c c c c c} \hline
**Key Cross Section** & **Condition 1** & **Condition 2** & **Condition 3** & **Condition 4** & **Condition 5** & **Condition 6** & **Condition 7** & **Condition 8** \\ \hline A (10\({}^{6}\) N) & 7.20 & 7.23 & 2.52 & 2.73 & 36.2 & 37.9 & 12 & 10 \\ B (10\({}^{6}\) N) & 24 & 23.5 & 5.90 & 8.45 & 31.2 & 32.4 & 7.87 & 8.50 \\ C (10\({}^{6}\) N) & 6.14 & 6.14 & 3.69 & 4.41 & 3.19 & 3.33 & 2.34 & 2.80 \\ D (10\({}^{6}\) N) & 6.16 & 6.16 & 3.71 & 4.44 & 3.26 & 3.36 & 2.41 & 2.85 \\ \hline \end{tabular}
\end{table} 
Table 4: Axial force at key parts of the structure in different conditions. \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Key Cross Section** & **Condition 3** & **Condition 4** & **Condition 5** & **Condition 6** & **Condition 7** & **Condition 8** \\ \hline A & \(-\)65.00\% & \(-\)62.24\% & 402.78\% & 42.20\% & 66.67\% & 38.31\% \\ B & \(-\)75.42\% & \(-\)64.04\% & 30.00\% & 37.87\% & \(-\)67.21\% & \(-\)63.83\% \\ C & \(-\)39.90\% & \(-\)28.18\% & \(-\)48.05\% & \(-\)45.77\% & \(-\)61.89\% & \(-\)54.40\% \\ D & \(-\)39.77\% & \(-\)27.92\%in the Kobe earthquake after setting the friction pendulum bearing. The seismic design code for buildings stipulates that the elastic-plastic inter-story displacement angle limit of a reinforced concrete frame-isolated wall is 1/100, so it still does not meet the seismic code standard. After setting the ring spring-friction pendulum bearing, the horizontal inter-story relative displacement of the structure dropped to below 3 cm, which meets the code standard. Tables 6 and 7 compare the maximum shear forces in the key section of the structure in the two earthquakes. First, the shear force of the mid-pillar reduced after setting the seismic isolation bearings. Among them, the shear of the mid-pillar reduced by 20% to 50% after setting the friction pendulum bearing, by about 10% to 20% after setting the ring spring bearing, and by more than 40% after setting the ring spring-friction pendulum bearing. However, the change rates of the three types of bearings on the side walls were different, which indicates that different bearings distribute the horizontal shear force of the structure in different ways, as shown in Figure 22. The upper end of the mid-pillar was subjected to about 5.3% of the horizontal shear force after setting the friction pendulum bearing, the upper end of the mid-pillar is subjected to 1.2-3.8% of the horizontal shear force after setting the ring spring bearing, and the mid-pillar is subjected to 0.5-2.1% of the horizontal shear force after setting the ring spring-friction pendulum bearing.