## 3 Experimental Phenomena and Result Analysis  
### Experimental Observations  
During the loading process, the lateral MTS hydraulic servo actuator is defined as positive when pushing and negative when pulling. When the TSPSW-M-1 specimen was  
Figure 5: Displacement collection device. Figure 6: Schematic diagram of strain gauge arrangement. Figure 7: Displacement loading curve. loaded to +1%, no significant deformation occurred (Figure 8a). When the load increased to +2%, local buckling began to appear at the corners of the steel plate. As the load continued to increase in a reciprocating manner, overall buckling of the steel plate occurred along the diagonal of the plate. During the reverse loading phase, the buckling path of the steel plate along the diagonal changed, the buckling locations at the corners shifted, and there was a relatively loud noise. After entering the elastoplastic stage, when the load increased to 4% (Figure 8b), the local buckling of the steel plate along the diagonal was already quite obvious, forming an overall buckling in the form of a diagonal tension band. At this point, the steel plate mainly exerted its post-buckling strength in the form of a tension band. When the load increased to 7% (Figure 8c), local failure of the steel plate occurred, mainly characterized by the shearing damage at the upper right end of the steel plate (Figure 9). After the test ended and the load was removed, the steel plate had irreversible out-of-plane residual deformation. Figure 10 presents the deformation states of the TCSPSW-M-1 specimen under different loading inter-story drift angles. When the loading was less than \(\Delta=+2\%\), no significant deformation was observed in the TCSPSW-M-1 specimen. When the loading reached \(\Delta=+4\%\), local buckling began to appear at the end of the diagonal of the TCSPSW-M-1 specimen (Figure 10b). The local buckling gradually increased with the increasing loading stage. When the loading reached \(\Delta=+6\%\), the TCSPSW-M-1 specimen had a significant  
Figure 8: TPSSW-M-1 specimen loading deformation diagram: (**a**) 1% interlayer displacement Angle, (**b**) 4% interlayer displace-ment Angle, (**c**) 6% interlayer displacement Angle, (**d**) 7% inter-layer displacement Angle. Figure 9: TPSSW-M-1 deformation status: (**a**) Deformation state of specimen under loading, (**b**) Deformation state of the specimen after disassembly. out-of-plane deformation (Figure 10c). During the loading process, intermittent noises could be heard from the specimen. As the loading inter-story drift angle increased to \(\Delta=+8\%\), the local buckling and out-of-plane deformation of the specimen continued to increase. However, unlike the regular flat steel plate specimen, the specimen did not form a distinct diagonal tension band. Instead, it formed a relatively shallow tension band along the corrugation direction at an angle of about \(10^{\circ}\) to the horizontal (Figure 10d). After unloading at the end of the test, the steel plate had irreversible out-of-plane residual deformation (Figure 11). Figure 12 illustrates the deformation states of the TCSPSW-M-2 specimen under different loading displacements. Similar to the TCSPSW-M-1 specimen, when the loading was less than \(\Delta=+2\%\), no significant deformation was observed in the TCSPSW-M-2 specimen. However, when the loading reached \(\Delta=+3\%\), local buckling began to appear at the end of the diagonal of the TCSPSW-M-2 specimen (Figure 12b). The local buckling gradually increased with the increasing loading stage (Figure 12c). When the loading reached \(\Delta=+6\%\), the TCSPSW-M-2 specimen had a significant out-of-plane deformation. When the loading increased to \(\Delta=+8\%\), the local buckling and out-of-plane deformation of the specimen continued to increase (Figure 12d). Throughout the entire loading process, no cracking or failure of the specimen occurred. After unloading at the end of the test, the steel plate had irreversible out-of-plane residual deformation (Figure 13).