## 5 Numerical Simulation
### Parametric Analysis  
The parametric analysis of the single parameter variation was performed based on the above numerical model with the design factors of RW1-2. The original parameters included the post-tension force factor; the number of SEDPs, \(\Delta_{\text{gap}}\), and the diameter of the MBSF with values of 0.5, 4, 7, and 24 mm, respectively, and the post-tension force factor referred to the ratio of the initial post-tension stress to the yield strength of the PT strands. The same loading protocol as the previous test was applied to the finite element model, and the skeleton curves were extracted from the obtained hysteresis curves with the same method as before, as shown in Figure 18.  
As shown in Figure 18a, the strength of the structure was positively correlated with the initial post-tension force, and the larger initial post-tension force offered stronger initial stiffness to the structure. It should be noted that as the initial post-tension force increases to a certain level, an abrupt change in the strength of the structure occurred at greater drift levels because the larger initial prestress results in the yielding of PT strands at greater drift levels. Once the PT strands in rocking structures yielded, the risk of structural failure and post-earthquake repairability extremely increased. Therefore, in the design of PRW-TSD system, the initial prestress should be limited under the premise of ensuring the initial stiffness of the structure. As shown in Figure 18b, the number of SEDPs significantly affected the strength of the structure, and a greater number of SEDPs caused a higher strength of the structure. In fact, the increase in the number of SEDPs enhanced the total shear bearing capacity of the coupling members in a coupled wall structure [35]. The increment in the total load-bearing capacity of SEDPs prolonged the range of the drift for the overall rotation of the two wall panels, the wall does of trailing wall were lifted to a larger height [47], and the MBSFs at these locations operated. Therefore, the growth in the number of SEDPs led to a decrease in the drift level corresponding to the abrupt change in the slope of the curve. Due to the effect of the number of SEDPs on the rotation mode of the wall in the structures with a great number of SEDPs, the PT strands in the trailing wall yield at a larger drift level. Consequently, during the design of the PRW-TSD system, the stress of PT strands should be checked if the number of SEDPs exceeded certain limitations.  
As shown in Figure 18c, the \(\Delta_{\text{gap}}\) had little effect on the strength of the structure, but the local enlargement of the skeleton curve showed that the growth of the \(\Delta_{\text{gap}}\) increased the drift level corresponding to the abrupt change in the slope of the curve, resulting in a relatively weaker strength of the structure at a larger drift level. It could be drawn that the MBSFs with reasonable gaps could yield at specifically-designed drift levels, at the slight expense of structural strength, and effectively reduce the repair cost after an earthquake. As shown in Figure 18d, the diameter of the MBSF affected the strength of the structure after the MBSF functioned with the same value of \(\Delta_{\text{gap}}\), and the larger diameter of the MBSF led to the greater strength of the structure. Therefore, the large diameter MBSF  
Figure 17: Comparison of the hysteresis curve for RW1-2.  
could effectively enhance the structural strength under major earthquakes. However, because of the non-negligible restraint effect of MBSFs with large diameters at wall toes, the flexural deformation of wall panels under horizontal earthquake forces may be increased to a certain extent. Considering the experimental phenomena of RW1-3, it is recommended that the design of the PRW-TSD system should be checked for cracks in the tensile edges of wall panels, considering the effect of MBSFs.