Structural Safety Analysis Of Through Supported Arch Bridge

CFST arch bridge with its excellent mechanical properties,convenient construction technology has got more and more attentions in the field of bridge construction,with the increase of the span and the structure innovation,and various accidental factors,such as a kind of CFST arch bridge construction is facing a huge risk,we must pay more attention,otherwise easily the accident caused the collapse,bring inconvenience to people traffic travel.Based on ANSYS,a single span 30 m concrete beam was established,and the effects of material,geometrical parameters,boundary conditions and physical parameters on the modal frequencies were studied.The results show that the material properties,geometric dimensions and boundary conditions have obvious influence on the modal frequency,so the damage of the modal parameters should be paid special attention to.The arch bridge across the canal southeast Xi Ying production bridge as an example,using finite element analysis software ANSYS to establish three-dimensional finite element model,analyzes the Xi Ying southeast cross channel bridge production in different temperature and different prestress,dynamic characteristics of arch bridge.When the temperature changes from-35 centigrade to 35 centigrade,the vibration mode of arch bridge is not obvious.When the ambient temperature increases,the vibration frequency increases with the increase of temperature,but decreases with the decrease of temperature.To study the camp southeast cross ditch bridge for example production expansion by applying different size under the condition of prestressed beam,influence on the dynamic characteristics of the bridge,with the increase of vibration frequency of prestressed will increase,that will change the performance of the prestressed arch bridge,which affects the vibration characteristics,but compared with smaller temperature effect.And the analysis of the mechanical properties when the Arch Bridge Suspender Damage and displacement,the change of Suspender Damage degree is generally greater than the tension rate,and can cause several adjacent Suspender Damage of suspender tension becomes larger,less impact on the unilateral Suspender Damage on the mechanical properties of the side arch bridge suspender,can not.Through the analysis of the vibration characteristics of arch bridge under different working conditions,finally found the bridge transverse vibration,vertical vibration and torsional vibration formation in turn,so that the vertical and torsional stiffness of arch bridge is significantly greater than the transverse stiffness.The reliability analysis of the important members in the structural system of the steel pipe arch bridge is carried out.The results show that the reliability of the suspender is the highest.However,in recent years,with the development of the steel arch bridge,most of the accidents are caused by the damage of the suspender.In practice,some measures should be taken to strengthen the safety monitoring to ensure the safe operation of the bridge.On the basis of the above analysis,this paper presents a set of early warning scheme for large scale concrete filled steel tubular arch bridge.