Dynamic Response Analysis of Prestressed Double-Layer Cable Flexible Photovoltaic Supports Brackets Under Fluctuation Wind Loads

To study the structural response of prestressed double-layer cable flexible photovoltaic brackets under fluctuation wind loads, an analytical solution for cable horizontal tension without considering temperature effects under uniformly distributed loads was obtained based on the energy variational method. A finite element model with a span of 30.48 meters was established, and the correctness of the model was verified. Based on the Davenport spectrum and considering the spatial correlation of fluctuating wind loads, the AR linear filtering method was used to simulate the time histories of fluctuating wind speeds. Applying 0° and 180° fluctuating wind loads at 7 nodes in the span direction, including 0, L/6, 2L/6, 3L/6, 4L/6, 5L/6, and L, consider the impact of P-Δ effects and large deformations, Perform nonlinear dynamic time-history analysis of structures was carried out. The results showed that the structural vibration mode was mainly Z-axis translational, and the first-order vibration mode frequency was 2.844 Hz; the fluctuating wind load in the X direction had an impact on the displacement responses of the structure in all three directions, with the X and Z directions having the greatest impact; the transverse and vertical stiffnesses of the structure were weak at the mid span, and the longitudinal stiffness at the support was weak; in the 180° wind condition, the displacement response range in the X-direction of the structure and the tension response range of the load-bearing cable increased by 20% compared to that in the 0° wind condition, The impact of the 180° pulsating wind on the structure was greater; the horizontal tension response of the structure did not show significant changes compared to the applied prestress, and the impact of fluctuation wind on the internal force of the prestressed double-layer cable flexible photovoltaic bracket was relatively small.