Study On Structural Behavior Of Third Yanhe Wujiang Cable-stayed Bridge With Special-shaped Pylon In Guizhou Province

With the advancement of the times,traditional cable-stayed bridges have been difficult to satisfy people’s pursuit of engineering aesthetics.Various unique shaped cablestayed bridges have emerged,but complex mechanical behavior problems are hidden behind the shaped towers.The Third Bridge of Wujiang river in Yanhe Tujia autonomous county is a(145 +160)m single-tower cable-stayed bridge.The bridge tower adopts a "flying pigeon" space-shaped cable tower,and the tower-beam pier adopts a fixed system.To this end,this paper takes the bridge as the engineering background,and studies the static and dynamic behavior of the cable-stayed bridge with the special-shaped cable tower and the stability of the special-shaped tower.Main tasks as follows:(1)Cable force optimization of cable-stayed bridge.The zero-displacement method and the formal-fit iteration method are used to optimize the cable tension of the cable and the initial tension of the construction phase.By analyzing the force of the hanging basket,optimizing the first and the second cable force during main deck construction.(2)Static analysis of a cable-stayed bridge with a different shape.Aiming at the problem that the stiffness of the structure of the tower after the consolidation of the main beam is small and the tensile stress is generated in some parts,the temporary combination structure of the tie rod,the cross bracing and the scissor support is proposed to enhance the stiffness of the tower and improve the cable.Stiffness during concrete construction and concrete stress.(3)Stability analysis of cable-stayed bridge.The "Flying Pigeon" shaped cable tower is adopted along the Third Bridge of Wujiang river.Based on the elastic theory,combined with the special functions of Bessel,Lommel and Airy,the combination of vertical uniform load and concentrated load is used.The formula of the elastic stability of the cable tower under the constraints of free and one-end consolidation and one-end elastic constraint is verified by the finite element method.Finally,the generality of the theoretical equation for the elementary function curve is determined for different cable towers.(4)Dynamic analysis of a cable-stayed bridge with a different shape.There are many parts with large changes in the stiffness of the special-shaped cable-stayed towers along the Wujiang River Bridge.The influence of the bridge self-vibration and the dynamics of the tower beam during the use of the bridge cannot be ignored.To this end,the selfvibration characteristics of the bridge tower are analyzed.The dynamic response of the internal force and displacement of the special-shaped tower and the main beam is studied according to the influence of vehicle coupling on the cable-stayed bridge of the specialshaped cable tower.