Wind Tunnel Tests of an Aeroelastic Model of a Long-Span Transmission Tower

Abstract

The modal analysis of a long-span transmission tower was carried out using a finite element method, and then its aeroelastic model was established by the discrete stiffness method for wind tunnel tests. The displacement and acceleration of the aeroelastic model were measured by a vision-based displacement measuring instrument and accelerometer, respectively. Also, the wind-induced responses of the tower were conducted by finite element calculation, with which the results of the wind tunnel tests are compared. The gust response factor was calculated and compared with those from the specifications and other studies. The results show that the vision-based displacement instrument can record well the vibration of the model tower in the wind tunnel. The acceleration of the tower is dominated by the first-order resonant response, whereas the displacement is dominated by the background response. The displacement and acceleration in the longitudinal and transversal directions are almost equal, indicating that the crosswind and along-wind responses are of the same magnitude. The displacement atop the tower obtained from the test after considering the Reynolds number correction almost coincided with that from the numerical simulation. The gust response factor of the tower obtained via wind tunnel tests is smaller than that of the codes and close to that found via finite element calculations.