The Wind Tunnel Tests And Wind Resistance Performance Studies Of Double Towers Self-Anchored Suspension Bridge

With the development of modern materials, design theories and construction techniques, the wind effects on bridges become more prominent as the structures grow with longer span and more flexibility. Wind load has been one of the control loads in the design of modern bridge. The characteristics of Self-Anchored Suspension Bridges give its status in the modern bridge system. However, as a sort of flexible construction system, it is necessary to study the wind resistance capability of the Self-Anchored Suspension Bridges in the stage of design and construction. A Self-Anchored Suspension Bridge, the SanChaJi Bridge across XiangJiang River in the north side of ChangSha, was carfully studied by means of combining the Finite Element Method with wind tunnel tests.The stiffening girder aerodynamics of SanChaJi XiangJiang River Bridge was analyzed by use of the CFD in ANSYS, By calculating the mean lift, drag and moment coefficients of the stiffening girder with three different fairing, while showing the pressure contour and streamline around the sections, the reason why these differences existed in static force were indicated.Dynamic characteristics of full bridge, main tower of SanChaJi XiangJiang River Bridge were evaluated respectively, which represented the dynamic characteristics of Self-Anchored Suspension Bridges.Wind tunnel sectional model tests of SanChaJi Bridge were implemented to determine it's critical wind speeds for flutter, flutter derivatives and vortex excitation. The test results indicated that the critical wind speeds for flutter well above the test wind speeds for flutter were obviously higher than for the bridge, and vortex excitation did not occur throughout the test wind velocities.In addition, full bridge aeroelastic model tests for this bridge were also carried out to investigate its wind resistance stability. The test indicated that the bridge has well whole wind resistance capability. Based on the results of calculations and tests, the wind resistance capabilities of Self-Anchored Suspension Bridges, a sort of construction system, were overall evaluated.