Influence of Tilt Angle and Sag-to-Span Ratio on the Wind-Induced Interference Effects on Structural Response in a Cable-Supported Photovoltaic Array

As a common large-scale civil engineering structure, cable-supported photovoltaic (PV) arrays are typically designed with a 25-year service life, with their primary structural system composed of beam-column frames, pre-tensioned cables and modules. Cable-supported photovoltaic arrays are susceptible to large-amplitude wind-induced vibrations (WIV), threatening structural safety and serviceability. This study investigates interference effects on an eight-row array that employs aeroelastic wind tunnel tests, focusing on how tilt angle and sag-to-span ratio influence vibration characteristics and interference mechanisms. Results show coupled vertical–torsional vibrations with amplitudes increasing with wind speed and that are more intense under wind suction than under wind pressure. Reducing tilt angle and sag-to-span ratio effectively suppresses vibrations and raises critical flutter speed. For interference effects, mean response demonstrates clear shielding with amplitudes decreasing leeward. In contrast, fluctuating response behavior depends on tilt angle: 5° tilt angle produces a shielding effect, while 25° tilt angle causes an amplification effect with periodic fluctuations. The 25° tilt angle shows greater sensitivity to wind speed, evidenced by decreasing interference coefficients from the second to eighth windward rows with increasing wind speed. Although reducing the sag-to-span ratio most effectively suppresses vibrations in the first windward row and consequently affects downstream interference coefficients, it does not alter the fundamental trends governed by tilt angle.