Analysis Of Stress Characteristic For Basket-type Concrete-filled Steel Tube Tied-arch Bridge

In this paper, the Zhengzhou Kaifeng inter city railway project DK14+579.57 Zhengzhou super large bridge as the engineering background, Using the Midas Civil software, Divided into construction stage to establish the three-dimensional finite element model of basket type CFST Tied Arch Bridge, has carried on the analysis to the stable performance and static performance of the construction and service stages,the parameters are analyzed in order of boom, boom structure and arch rib. The main conclusions are as follows:(1) The beam is always under compression in the stress stage, and the overall performance of the beam is larger in the end of the beam. In addition to the tension stage, the stress of the system decreases with the increase of the load, and the bending moment of the beam at each construction stage is larger than that at the beam end.Compared with the tie beam, arch rib’s internal force in construction and completion stage is always very small, showing typical rigid flexible beam arch characteristics; in the construction and use phase, Department of girder and arch rib of the stress and deformation shall meet the requirements of the code.(2)The system of small changes in the values of changes in the values of and(2)and the installation sequence compared to the hangers are installed at intervals, the girder and arch rib of the link is weak, but beam cross regional steel vault area moment distribution is uniform, with Nielsen suspender system compared to parallel suspender system of beam and arch rib is weak, and the tie beam and arch rib of the bending moment and live load moment, deflection and live load deflection compared with Nielsen system, but the axial force had no significant difference; constant load Nielsen system steeve tension, but live load fatigue stress amplitude is higher; the static performance of arch bridge with parallel arch rib system and inclined arch rib system is not very different..(3) Super large bridge of Zhengzhou basket type CFST Tied Arch Bridge under the condition of fifth order instability mode are the same, and lateral side of the archrib stability. The stability safety coefficient of the Nelson boom system is larger than that of the parallel boom system, and the stability safety factor of the inclined arch rib system is larger than that of the parallel arch rib system.