## 3 Test Results and Analysis
### The Structural Dynamic Response Analysis  
Table 7 shows the measured peak stress at each measuring point in the structural inner layer. It can be seen from Table 7 that the peak stress distribution at each measuring point in the inner layer of the same structure is not uniform. The maximum peak stress lies at the measuring point in the inner layer of the arch spring, and the stress concentration is obvious. When the strain value caused by peak stress exceeds the deformation resistance of the structure, the arch spring is more likely to be damaged relative to the other positions of the structure. In order to quantitatively compare the advantages and disadvantages of the three types of structures, a dimensionless stress reduction effect factor is defined, that is  
\[b=(S_{i}-S_{\Sigma i})/S_{i}\]  
where \(S_{i}\) is the peak stress at point \(i\) in the reference structure test section that is named as the C30 reinforced concrete test section, \(S_{\Sigma i}\) is the peak stress at the corresponding measuring point \(i\) in the comparison structure test section \(\Sigma\), and \(b\) is the stress reduction rate of the measuring point \(i\) in the comparison structure test section to the reference structure test section. The closer the value \(b\) tends to 1, the better the stress reduction effect of each measuring point in the comparison structure test section is. On the basis of Table 7, the peak stress of each measuring point on the cross section of the straight-wall-arch structures is fitted to obtain the distribution rule of the peak stress along the key measuring points of the cross-section of the arch structure, as shown in Figure 12. It can be seen from Figure 12 that, comparing with the C30 reinforced concrete test section, the peak stress values of the inner layer of the high-performance reinforced concrete test section, and the composite structural test section in the vault, the hance, the straight wall midpoint and the floor midpoint, all show a decreasing tendency. The peak stress of the inner layer of the floor in the C30 reinforced concrete test section is 15.71 MPa, and the attenuation effect factors of the high-performance reinforced concrete test section and the composite structural test section are 27.7% and 38.7%, respectively. Although the three types of structural test sections do not achieve the structural compression shear damage states, the three types of structural tests show the characteristics of uplift and extension failure on the floor. This is mainly caused by the diffraction when the plane compression wave propagates to the free surface of the structure, and the diffraction wave and the compression wave propagating to the floor are superimposed. When the stress of the reflected tensile wave exceeds the allowable dynamic tensile value of the structure, the floor will be pulled and cracked. On the whole, the floors of the three test sections bear relatively uniform loads transmitted by the two straight walls, and the floors basically show the characteristics of symmetrical damage and bending damage. \begin{table}
\begin{tabular}{c c c c c c} \hline \multirow{3}{*}{**Measuring Point**} & **C30 reinforced Concrete Test Section** & \multicolumn{2}{c}{**High-Performance Reinforced Concrete Test Section**} & \multirow{3}{*}{**Composite Structure Test Section**} \\ \cline{2-2} \cline{4-6}  & **Peak Stress (MPa)** & **Peak Stress (MPa)** & **Stress Reduction Effect Factor** & **Peak Stress (MPa)** & **Stress Reduction Effect Factor** \\ \hline Vault & 22.88 & 15.81 & 30.9\% & 8.74 & 61.8\% \\ Hance & 33.72 & 19.78 & 41.3\% & 8.89 & 73.6\% \\ Arch Spring & 42.31 & 52.74 & \(-\)24.6\% & 22.56 & 46.7\% \\ Straight Wall & 29.45 & 22.21 & 24.6\% & 12.98 & 55.9\% \\ Floor & 15.71 & 11.36 & 27.7\% & 9.63 & 38.7\% \\ \hline \end{tabular}
\end{table} 
Table 7: The peak stress of each measured point in the structural inner layer.