## 2 Methodology  
A photovoltaic power generation project located in Hubei Province, China, spans approximately 1000 acres. This project employs the operation mode of the fishery-photovoltaic complementation and has an annual power generation capacity of 40 MW. Two types of array arrangements were adopted, with the photovoltaic panel surface installed at an angle of 15\({}^{\circ}\). Array A consists of 2 vertical rows and 26 vertical columns, with 52 photovoltaic panels per group of supports, supported by 7 single columns. Array B consists of 2 vertical rows and 13 vertical columns, with 26 photovoltaic panels per group of supports, supported by 4 single columns. Precast high-strength concrete pipe piles with a concrete  
Figure 2: Photos of photovoltaic support damage. strength grade of C80 are utilized as the foundation of the photovoltaic supports. Schematic diagrams of the support structures are shown in Figure 2(a),b. The photovoltaic supports used in Arrays A and B share identical components, with Q355B-grade steel utilized for the columns and Q420B-grade steel used for the purlins, beams, and braces. C-shaped steel was employed for the columns, beams, and purlins, with cross-sectional specifications of C80 \(\times\) 40 \(\times\) 12 \(\times\) 2.5, C70 \(\times\) 40 \(\times\) 15 \(\times\) 2.0, and C105 \(\times\) 50 \(\times\) 15 \(\times\) 1.6, respectively. The letter \"C\" indicates the use of C-shaped steel as the cross-sectional profile of the components, with the parameters illustrated in Figure 2(c). For the braces, round steel pipes with a diameter of 50 mm and a thickness of 1.6 mm were used, as shown in the schematic diagram in Figure 2(d). The columns were welded to the embedded steel components of the concrete foundation, while bolt connections were used to join the columns, purlins, beams, and braces. Photovoltaic panels were secured to the purlins using bolts. L-shaped steel was employed for the purlin hanger to connect the purlin and the beam. To facilitate construction, the ends of the round steel pipe braces were flattened and connected to the beams and concrete foundation. Specifically, the beams and purlins were joined using purlin hangers, as illustrated in Figure 4.  
After the project was put into operation, significant deformation was observed at the joints of the photovoltaic supports. This deformation is primarily manifested as the rotation of the purlin hangers and bending at the ends of the braces. In some photovoltaic  
Figure 4: Photovoltaic support component connection types. Figure 3: Schematic diagram of photovoltaic support. supports, the purlin hangers rotated around the bolt by nearly 90\({}^{\circ}\), as shown in Figure 5, resembling a failed on-site experiment. The unexpected deformation highlighted an urgent need to identify its causes to ensure the structural safety of the supports and minimize investment losses. The observed failure phenomena exhibited certain patterns. The deformation mainly occurred at the joints connected by a single bolt between the purlin hanger and the purlin, whereas the supports connected by two bolts exhibited significantly less deformation. To investigate the cause of the deformation, various factors were thoroughly analyzed. 1. Experimental analysis was conducted on the steel materials used in the project, and the results indicated that the section dimensions and mechanical properties of the support components largely conformed to the design requirements. 2. The load calculations in the structural design process were examined, and a comparison was made between the major load values for photovoltaic supports as specified in Chinese codes [23; 24; 32], American codes [19; 20], and Eurocodes [21; 22]. Additionally, SAP2000 was used to analyze the load-bearing capacity and deformation of the photovoltaic supports. 3. The finite element analysis (FEA) software ABAQUS (V6.14-5) was used to analyze the impact of different component connection designs on the deformation of photovoltaic supports.