## 2 Design and Analysis of Decorative Panels
### Structural Analysis
#### 2.2.2 Analysis of Decorative Panels  
Before self-bending tests, a full-scale 3D numerical model of the decorative panel in the last concrete cantilever segment was developed using ABAQUS 2018, as shown in Figure 4. In this model, the panels were simulated using shell elements. Since the primary objective of this simulation was to identify the position with the highest stress response for subsequent crack resistance testing, the panel material in ABAQUS was assumed to be elastic. The modulus of elasticity and expansion factor of shell elements were set at 40 GPa (UHPC) and \(1\times 10^{-5}\), respectively. The frictional energy-dissipating connections between the main girders and panels were simulated using non-linear spring elements. The vertical degrees of freedom of these connections were constrained. The deformation parameters of frictional energy-dissipating connections were determined via a full-scale push-out test. The load vs. relative displacement in the shear direction of the connection is shown in Figure 5. The maximum static frictional force and ultimate shear force are 7.475 kN and 84.900 kN, respectively. Subsequently, the individual and combined load actions were applied to the panel model to obtain the stress responses. These loads included the forced deformation induced by the main girder, wind loads, self-weight, and temperature effects. The values and types of the loads as well as the stress responses are presented in Table 5. The wind load on the decorative panels was determined by referring to GB50009-2012 [25]. The forced deformation value was equal to the vertical deformation of the last concrete cantilever in Table 4. Other load values were determined by the same standards as before. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Segment** & **Transverse (mm/m)** & **Vertical (mm/m)** & **Longitudinal (mm/m)** \\ \hline Last concrete & 0.021 & 4.8 & 0.78 \\ cantilever & & & \\ Pier top & 0.04 & 0.97 & 0.15 \\ Steel girder midspan & 0.02 & 0.4 & 0.44 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Deflections of key segments of the bridge. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Load Type** & **Load Value** & **Combination** \\  & & & **Coefficient** \\ \hline Dead load & Self-weight & 26 kN/m3 & \\ Dead load & Secondary dead & 62 kN/m & 1.0 \\  & Lane & 10.5 kN/m & \\ Vehicle load & Vehicle concentrated & 360 kN & 0.4 \\ Temperature & Temperature lifting & \(\pm\)20 \({}^{\circ}\)C & 0.5 \\  & Temperature gradient & Table 3 & \\  & Support settlement & 10 mm & 1.0 \\  & Shrinkage and creep & JTG 3362-2018 & 1.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Load details of bridge. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Height (m)**} & \multicolumn{2}{c}{**Positive (\({}^{\circ}\)C)**} & \multicolumn{2}{c}{**Negative (\({}^{\circ}\)C)**} \\ \cline{2-5}  & \(\mathbf{T_{1}}\) & \(\mathbf{T_{2}}\) & \(\mathbf{T_{3}}\) & \(\mathbf{T_{4}}\) \\ \hline
0–0.1 & 25 & 6.7 & \(-\)12.5 & \(-\)3.35 \\
0.1–0.2 & 6.7 & 4.47 & \(-\)3.35 & \(-\)2.235 \\
0.2–0.4 & 4.47 & 0 & \(-\)2.235 & 0 \\
0.4–0.7 & 0 & 0 & 0 & 0 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Temperature gradient in the bridge cross-section. As shown in Table 5, the tensile stresses individually induced by the self-weight, wind load, and temperature were relatively smaller than those induced by the forced deformation because the deformation caused by the bridge was considerable and led to the greatest tensile stress in the panel. The stress patterns of the panel model in two directions are shown in Figure 6. It can be identified that the curved section and connection position saw the greatest tensile stress. However, the connection position was always thickened locally in practical engineering, resulting in smaller tensile stress. Thus, the stress of the curved section was investigated in this study. Figure 4: Numerical model of the decorative panel at the last concrete cantilever segment.