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Parallel bridges subjected to aerodynamic interference can experience wake-induced vibrations (WIVs) within the wind speed range allowed for vehicle operation, affecting ride comfort, and running safety. Wind tunnel tests are conducted to obtain vertical and torsional WIV responses of the leeward railway bridge, and aerodynamic coefficients for both the bridge and the suburban railway vehicle. Displacement-based and harmonic wake-induced force models are developed, and a novel WIV–WVB (Wind–Vehicle–Bridge system considering WIV responses) analysis model is proposed. The analysis focuses on the effects of factors such as buffeting forces, WIV mode orders, bridge entry time, and WIV amplitude on running performance. Results show that the vertical and torsional WIV responses are reproduced using both wake-induced force models align well with test results. At higher wind speeds, the difference in vehicle dynamic responses with and without buffeting forces becomes pronounced. Vertical WIV significantly elevates the vertical acceleration (up to 59.1%) and offload factor (up to 42.9%), while lateral vehicle dynamic responses remain largely unaffected. Higher mode orders further amplify the increases in vertical acceleration and offload factor, and these responses become more sensitive to changes in vehicle speed. Torsional WIV elevates all vehicle dynamic responses, particularly increasing vertical and lateral accelerations by 53.5% and 30.2%, respectively. At constant torsional WIV amplitude levels, vehicle responses exhibit greater sensitivity to changes in vehicle speed and are less influenced by wind speed variations. Vertical acceleration is highly sensitive to changes in vertical and torsional WIV amplitude and is the first to exceed the limit as amplitude increases. [ABSTRACT FROM AUTHOR]

The sting support faces an issue of being prone to resonance due to its low-damping characteristics, which will compromise the accuracy of test data in wind tunnel experiments. Magnetorheological damper (MRD)-based tail support (MRSS) features varying stiffness and damping abilities, enabling it to suppress the vibration with random, time-variation characteristics in a self-adaptive way, and it also exhibits excellent fail–safe properties. This work aims to validate its controllability and fail–safe property in a wind tunnel environment. First, the natural frequency, root mean square (RMS), and power spectral density (PSD) of the designed MRSS' response for random excitation were theoretically analyzed. Then, wind tunnel experiments were conducted to test the response under different attack angles, wind speeds, and test currents. Subsequently, the controllability and fail–safe property were demonstrated by analyzing the aircraft model response. Also, the variable stiffness and damping properties of MRD behind the observed phenomena were revealed based on the theoretical analysis. Results demonstrate that as the input current increases and the MRD's stiffness continues to increase, the damping initially increases and then decreases. Increasing wind speed leads to a decrease in the MRD's stiffness. Additionally, approximately 50% reduction in RMS and a multi-modal response attenuation was achieved. [ABSTRACT FROM AUTHOR]

The double-layer (DL) cable-supported photovoltaic (PV) module system is an emerging type of structure that has garnered significant attention in recent years due to its large span, strong terrain adaptability, and economic advantages. As it is a flexible structure supported by cables, wind-induced vibrations can lead to structural instability or even component damage, posing a serious threat to the safety of PV power plants. Determining the wind-induced vibration characteristics of the DL cable-supported PV module system is the foundation for ensuring its structural safety. In this study, based on wind tunnel tests performed on an aeroelastic model, a typical DL cable-supported PV module system used in a real engineering project was examined. The wind-induced displacement and torsional vibration characteristics of the model were compared and analyzed under different wind speeds. The shading effects of the PV array were also studied, and the impact of different wind angles and the initial tilt angles of PV modules on the wind-induced vibration characteristics was revealed. The results show that the greatest displacement vibration response occurs in the vertical direction; in comparison, displacements in other directions are smaller. Wind-induced torsional vibrations are negligible and can be ignored compared to displacement vibrations. The wind-induced vibration of the first row in the cable-supported PV array is significantly greater than that of the subsequent rows, and the shading effect is obvious. In the same row, the displacement vibration of modules at the center span is greater than at the sides. Different wind angles and initial PV module tilt angles affect the wind-induced vibration characteristics. When the wind direction is perpendicular to the cables and wind suction occurs, the wind-induced vibration is maximal. Within a limited range, the larger the initial tilt angle of the PV module, the greater the wind-induced vibration. [ABSTRACT FROM AUTHOR]