# Proposed New Analytical Method of Tower Load in Large-Span Arch Bridge Cable Lifting Construction
## 4 Application in Tower Analysis
### Load-Carrying Capacity  
The tower is a structure under pressure and bending in the whole, and the load-carrying capacity of each member of the tower is worthy of attention. Due to the complex structural composition of the internal components of the integrated system of a cable tower and buckle tower, strength analysis of the main components is required. Figure 8 shows the main components of a tower. The tower is mainly made of universal rods that are  
Figure 12: First six orders of buckling mode characteristics of towers: (**a**) buckling mode 1; (**b**) buckling mode 2; (**c**) buckling mode 3; (**d**) buckling mode 4; (**e**) buckling mode 5; and (**f**) buckling mode 6. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Load Condition** & **Buckling Factor** & **Load Condition** & **Buckling Factor** \\ \hline
1 & 8.01 & 5 & 7.52 \\
2 & 8.02 & 6 & 7.53 \\
3 & 8.15 & 7 & 22.91 \\
4 & 8.16 & 8 & 23.13 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: First-order buckling factor of the towers for each load condition. connected by bolts. Figure 13 shows the maximum axial force diagram of the universal rods of a cable tower and the buckle tower located on the right bank. The maximum axial force of the universal rods of the cable tower occurs under the action of load condition 4, and the maximum axial force of the universal rods of the buckle tower occurs under the action of load condition 2. Figure 13a shows that the maximum axial force in the universal rods of the cable tower occurs in the vertical rods located at the left-center-right positions. The axial force of the universal rods in the middle of the cable tower is the largest, which is because under the action of load condition 4 the middle main cable bears the rated load and transfers the vertical pressure to the vertical universal rods in the center of the cable tower. Figure 13b shows that the universal rods with higher axial force in the buckle tower are diagonal rods, and the maximum axial force occurs in the diagonal rods at the top of the buckle tower. Due to the relatively dense arrangement of the diagonal rods between the steel pipe columns, the axial force of the universal rods located in this area is relatively small. The maximum axial forces of the tower's universal rods are listed in Table 10.  
As can be seen from Table 10, the axial force of all types of universal rods in the cable tower is greater than that of the buckle tower. The maximum axial force of the vertical rod of the cable tower is \(-2362.262\) kN, and its allowable axial force is \(-2660\) kN, which is not a high degree of safety redundancy. The difference between the axial force of the diagonal and horizontal rods of the cable tower is not large, and their safety redundancy is not high. Therefore, in the process of tower design, engineers should strive to find a balance between increasing the safety redundancy and reducing the self-weight of the structure. The axial force of all types of universal rods in a buckle tower is relatively small compared to a cable  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Name of Component**} & **Maximum** & **Allowable** & **Maximum** & **Allowable** \\  & **Axial Force** & **Axial Force** & **Name of Component** & **Axial Force** & **Axial Force** \\ \hline \hline \multirow{2}{*}{Cable tower vertical rod} & \(-2362.262\) & \(-2660\) & Buckle tower vertical rod & \(-523.017\) & \(-1330\) \\ \cline{1-1  
tower, and the safety redundancy is larger. This is because the vertical load transferred by the hinge seat distribution beam is mainly shared by the steel pipe column of the buckle tower, while the universal rod shares less. The maximum axial force of the universal rods of the buckle tower occurs mainly in the diagonal rods, where the maximum axial force is \(-523.017\) kN.