###### Abstract  
The large-span bridge is highly sensitive to temperature and wind loads. Therefore, it is essential to study the bridge's fatigue life under the combined effects of temperature and static wind loads. This study focuses on the main bridge of Qiao Jia-fan 2# on the Yinkun Expressway (G85), with a span of 250 m and a configuration of a PC composite box girder bridge with corrugated steel webs. Firstly, on-site temperature and wind direction measurements with wind speed were conducted at the bridge site. Origin 2022 software is used to make mathematical statistics on the data, the representative values of atmospheric temperature difference between day and night and the basic wind speeds are calculated. Secondly, based on the basic wind speed in the most unfavorable wind direction, the static three-component force coefficients of bridge at different angles of attack are calculated by FLUENT 2022 R1 software. By comparison, the most unfavorable wind angle of attack, wind direction and wind load value of Qiao Jia-fan 2# Bridge are obtained. Finally, the finite element software MIDAS/FEA NX 2022 is used to analyze the fatigue life of the main bridge of the Qiao Jia-fan 2# Bridge. The analysis results show that the representative value of the temperature difference between day and night in the area where PC composite box girder bridge with corrugated steel webs is located is 22 \({}^{\circ}\)C, the most unfavorable wind direction is NNE wind direction, and the most unfavorable wind attack angle is 3\({}^{\circ}\) wind attack angle. It is found that the maximum stress of concrete and corrugated steel webs appears near the 0# block, and the life of corrugated steel webs is far greater than that of concrete. PC composite box girder bridge with corrugated steel webs; temperature; static wind load; finite element; fatigue analysis +
Footnote †: journal: Applied Sciences  
condition may exceed the design estimation, which leads to an impact on the durability of the bridge. It is reported that many bridges in the world have fatigue cracks or even brittle fractures during operation, so it is necessary to study the fatigue life of bridges [2; 3; 4; 5; 6; 7]. In recent years, significant research has been conducted on the fatigue behavior of Prestressed concrete box girder bridge with corrugated steel webs. [PERSON] et al. [8] and [PERSON] et al. [9] both investigated plate girders with trapezoidally corrugated webs and studied their fatigue performance. They examined stress concentrations, identified causes of fatigue cracking, and proposed techniques for determining the fatigue life of these girders. The studies assessed various factors such as corrugation profile, stress ratio, combined stresses, and weld size, providing valuable insights for optimizing the design of girders with corrugated webs. Additionally, [PERSON] et al. [10] explored the impact of additional normal stresses on the bending resistance of girders with corrugated webs, highlighting the differences in stress distribution compared to conventional I-girders. These studies aim to enhance our understanding of the fatigue and bending behavior of corrugated web girders, ultimately improving our knowledge of their structural performance. At present, the research on wind load of bridge structure is mainly concentrated on suspension bridge and cable-stayed bridge, and the research on wind load effect of long-span PC composite box girder bridge with corrugated steel webs is relatively insufficient. In addition, considering that the bridge has different longitudinal and transverse dimensions, the current bridge wind resistance specifications are usually considered in accordance with the full wind direction. However, this approach fails to fully consider the difference of wind load on the bridge structure under different wind directions. Therefore, it is necessary to distinguish the wind direction more carefully to evaluate the wind speed of the bridge in all directions more accurately, so as to improve the accuracy and safety of the design.