Study on One Special-shaped Long-span Arch Bridge Using Wind Tunnel Test

摘要

Study on wind-resistant performance of one special-shaped long-span arch bridge is carried out using a full-bridge aeroelastic model with a scale of 1:66 in wind tunnel test. The tests on vortex-induced vibration (VIV for short), buffeting and aerodynamic stability of both bare arch and full-bridge are comprehensively conducted in smooth and turbulent flows with attack angle of -3°, 0°, 3°, and yaw angles ranging from 0°to 180° with a step of 15°. The results show that the first-order symmetric VIV of vertical bending appears on the bare arch in smooth flow with attack angle of -3°, 0°, 3°, and yaw angle of 0°, 5°. The maximum amplitude of VIV at 1/4 section of the bare arch is close to 30 cm, higher than the corresponding value at the crown section. No stable VIV is observed on full-bridge model tests in both smooth and turbulent flows. For full-bridge model in turbulent flows, both means and standard deviations of girder torsional displacement at 1/2 and 1/4 sections are very small, which prove that the bridge integral torsional stiffness is significantly improved due to the 3-D cable-support system. The bridge possesses good aerodynamic stability for both bare arch and full-bridge service states.