A Study On Control Measures Of Wind-induced Buffeting Response During The Construction Of Zhongjian Super Large Bridge (Steel Truss Girder Cable-stayed Bridge)

With bridge span constantly widens and wide application of new material and structure,and optimization of manufacturing technology,the stiffness and damp of bridge structural system shows a clear downward trend,the sensitivity of the bridge structure to the action of atmospheric wind is become more and more outstanding.The wind-induced vibration will inevitably affect the safety of the bridge structure and construction,and this problem is must be solved.Therefore,it has a important engineering practice significance to study the control measures during the wind-induced buffeting response of bridge construction.This paper relies on Zhongjian Bridge of the Enshi to Laifeng express high way in Hubei.According to the structural characteristics of steel truss girder of cable-stayed bridge,wind-induced buffeting response control measures for steel truss girder of large bridge during construction were studied.The development history of long span cable stayed bridges at home and abroad is expounded firstly in this paper,introduces the theoretical basis and research status of bridge buffeting and research progress of construction wind vibration control of steel truss girder cable stayed bridge.Then introduces the common measures to control the wind-induced vibration of bridge,and the design parameters of the steel truss girder cable stayed bridge with the background project are introduced briefly,and clear the mechanical measures of wind cable as the focus of the study of bridge construction period the wind-induced vibration control.On this basis,the design basic wind velocity of the main beam of the bridge construction phase is determined by reference specification requirements.The three component coefficients of Steel Truss Girders of ZhongJian super large bridge were obtained by using the large general fluid analysis software FLUENT.At the same time,A finite element model of the structure of ZhongJian super large bridge was built by using ANSYS,The MATLAB program was used to generate the time history samples of the fluctuating wind field and Bridge buffet load,and the result were into ANSYS model for structure dynamic response analysis.The wind-induced response of static wind and buffeting response during steel truss cable-stayed bridge construction in the two typical state of maximum single cantilever and maximum double cantilever were calculated and analyzed respectively.The static wind deformation and vibration suppression effect of the wind cable to the typical construction condition of steel truss girder of cable-stayed bridge with steel truss girder are studied.The main work includes the following aspects:(1)When the wind cable is not set,the maximum static wind displacement of the maximum single cantilever state of the steel truss girder occurs at the end of the cantilever.(2)When the wind cable is not set,the maximum double cantilever state has a larger cantilever end to the main girder of the main girder,and the larger chattering displacement leads to a greater response to the internal force of the main girder.(3)The wind cable can effectively restrain the static wind displacement of the steel truss girder.The different section area of wind cable have different effects.The larger the section area of wind cable,the better the resistance effect.Under the same condition of wind cable section area,the program A can better restrain the deformation of steel truss girder under the action of static wind than program B.(4)The wind cable can effectively restrain the wind-induced buffeting response of the steel truss girder at construction stage.The larger the section area of wind cable,the more obvious the effect of the wind cable on the chattering displacement and internal force of the main beam.Under the same condition of wind cable section area,the program A is better than program B in restrain buffeting displacement and buffeting inner forces of the main beam.