Continuous Beam Railway Arch Combination Of Structural Design Of Key Technologies

Continuous beam arch combination bridge was emerging with railway construction in China.lt combines long span continuous girder with arch to form a combined structure,which has several significant advantages for its great structure stiffness, excellent dynamic stability,large span,attractive appearance and easy application.According to spatial solid model and spatial grillage model of Kunyang bridge constituted by some finite element analysis softwares which was constructed on Wenzhou-Fuzhou railway,study spatial mechanics features of continuous beam arch combination structure, establish models of continuous beam arch combination bridges with different design parameters and compare and analyze their spatial structure stabilization,discuss spatial structure stabilization of continuous beam arch combination structure affected by those design parameters.The research will have referenc value on the design of such kind of bridges in the future. This dissertation has mainly dealt with the following respects:(1)According to overall mechanical properties of continuous beam arch combination structure,study cooperation mechanic between beam and arch for continuous beam arch combination structure with analytical method,quantitatively work out the ratio of bending moment sharing between beam and arch r,the ratio of load ratio shared by arch t,tension and pressure of beam and arch and section bending moment of beam and arch,and then compare them with the results calculated by finite element software.Discuss the effect on r and t by ratio of bending stiffness of beam and arch, ratio of rise to span, suspenders axial deformation coefficient and ratio of separation distance of suspenders.Reveal cooperation mechanic between beam and arch for continuous beam arch combination structure.(2)Study transverse stresses of top plates affected by span of box girder bridge,longitudinal position,cross sectional depth and web thickness etc.By Ansys entity unit model of Kunyang birdge,discuss the distrubution rule of transverse stresses of top plates along the longitudinal and transverse positions on side span cross section and middle span cross section, suspender area and no suspender area,and then compare it with the results calculated by rigid supported frame method which is used commonly.(3)Establish the grillage model of the whole Kunyang bridge,and prove that its stabilization can meet normative requirements under dead load and moving load whilie operation stage.Meanwhile,discuss spatial structure stabilization of continuous beam arch combination structure affected by ratio of rise to span,the angle of toe-in of the arch rib and forms of lateral brace.