Wind tunnel test for static wind loads and vortex-induced vibration characteristics of steel truss arch rib

This paper takes a domestic long-span steel truss arch bridge as research background,investigating the static wind loads and vortex-induced vibration characteristics of steel truss arch rib.The three-component coefficients and vortex-induced vibration characteristics of 1/4 span and 1/2 span arch rib sections are tested by section model wind tunnel test,and the properties of three-component coefficients about the sections of steel truss arch rib are investigated.Based on the results of wind tunnel test,the empirical function with regard to the drag coefficient of arch rib are developed,and the Strouhal numbers of 1/4 span and 1/2 span arch rib sections are calculated.The results show that the wind attack angle has small effect on the three-component coefficients.The drag coefficient can be described by exponential function about height,although lift coefficient and pitch moment coefficient do not change with the increasing height.The vortex-induced vibration characteristics of steel truss arch rib are well.The Strouhal numbers are smaller and the wind speeds of vortex-induced vibration are larger under different wind attack angles.However,the structural damping ratio has significant impact on the vortex-induced vibration characteristics.