# A Component-Based Model for Novel Modular Connections with Inbuild Component
## 2 Parameter Analysis
### Parameter Analysis Results
#### 2.3.4 Allowable Construction Errors  
In order to guide the design of joints accurately, it is necessary to analyze the influence degree of different construction errors on mechanical properties of connections. In this section, 1 mm, 2 mm and 3 mm were selected as the control group based on the reference model of 0 mm construction error. The moment-rotation curves of connections with different construction errors were shown in Figure 21. Compared to the reference model G0, the initial stiffness of G1, G2 and G3 models decreased by 29.8%, 41.7% and 48.7%, respectively, and the ultimate bending capacity decreased by 1.1%, 1.5% and 2.2%, respectively. Increasing the construction error had a great effect on the initial stiffness of the connection but had almost no effect on the ultimate bearing capacity.  
Figure 19: Continuity index-moment curves of connections: (**a**) The height of inbuild component; (**b**) The thickness of inbuild component.  
Figure 18: Moment-relative dislocation t curves of connections: (**a**) The height of inbuild component; (**b**) The thickness of inbuild component.  
Figure 22 showed moment-dislocation (M-g) curves with different allowable errors, and there were significant morphological differences among the curves. In the initial stage of the G0 model (moment was less than 200 kNm), dislocation grows almost linearly and slowly. The curve of the G1 model increased linearly in the initial stage, and the slope was about 78% lower than that of the G0 model. When the bending moment reached 80 kNm, a slip segment of about 0.5 mm appeared in the curve, and then the curve continued to maintain a linear growth before 200 kNm. A 1 mm horizontal slip segment appears at around 80 kNm of the G2 model, and then the curve changes back to a linear growth mode. The G3 model curve almost overlaps with the G2 model in the initial stage. When the bending moment reached 100 kNm, the curve showed a slip segment of about 3 mm. The dislocation of the G1, G2 and G3 models were 2.9 mm, 4.4 mm and 6.2 mm at ultimate moment, which were 86.6%, 185.5% and 305.3% higher than that of the reference model G0, respectively. The construction error has a significant effect on the relative displacement of the upper and lower columns.  
Figure 21: Moment-rotation curves of connections with different construction errors.  
Figure 20: Stress distribution of inbuild component with different thickness.  
Rotation difference-moment curves of the G0 to G3 models were shown in Figure 23. Before 100 kNm, the curves of the G1, G2 and G3 models almost coincide and are higher than those of the G0 model, indicating that the continuity of connections with construction errors in the elastic stage was similar and weaker than that of the model without admissible errors. When the bending moment was greater than 200 kNm, the curves of the G2 model and the G3 model showed a divergent trend, and the rotation difference continued to increase, while the G0 model and the G1 model remained at a low level. Through the above analysis, it is found that the construction error has great influence on the initial stiffness, the dislocation and the continuity of the connection. Mises stress distribution at each connection was shown in Figure 24 at the moment of 100 kNm. For the G0 model, the inbuild component was closely attached to the column wall, which increases the strength of the joint panel and thus improves the initial stiffness of the node. For the G1 to G3 models however, the stress distribution still remains in a low level, indicating that the connection was in a \"slip\" stage.  
Figure 23: Continuity index-moment curves of connections with different construction errors.  
Figure 22: Moment-relative dislocation curves of connections with different construction errors.