The Whole Stability Analysis Of Concrete Cable-stayed Bridge

With the increasing cable - stayed bridge span and the thinner box girder, thestructure stiffness decrease both overall and partly. Because of the cable-stayed, thebridge towers and the main beam have to withstand great axial forces, which makethe stability of cable-stayed bridge become much more important. This paper takinga concrete cable-stayed bridge in engineering practice as engineering background,based on the stability theory of two classes and the nonlinear theory, the stabilityproblem of a long span concrete cable-stayed bridge is studied. The main work ofthis paper is as follows:(1) Expound the geometric nonlinear and the material nonlinear theory in cable- stayed bridge, and the approaches were also discussed. Introduced the substantialdifferences between the first class of stability problems and the second class ofstability problems, the finite element solving method and the criteria.(2) Detailed description of the rigidity, quality, boundary conditions, geometricnonlinear and material nonlinear processing of structure; established the singlemain girder model and double main girder model to analysis the overall stability ofconcrete cable-stayed bridge.(3) Simulating whether the cable tower header crossbar, lateral stiffness ofconnection between the tower and the beam, lateral stiffness of connection betweenthe pier and the beam exist, to discuss the overall stability influence in differentlateral stiffness and different main beam cross section, then made some positiveproposals.(4) Studied the first class of stability during the whole construction process,and reckon in the geometric nonlinear, material nonlinear influence to study thesecond classes of the stability in the maximum cantilever, the largest singlecantilever, middle span joint, second stage constant load stage.(5) Analyze the first class of stability and the second class of stability in fivedifferent operational stages, the geometrical nonlinearity and the geometrymaterials double nonlinear were included in the second class of stability analysis.