Research On The Stability Of Multi-Tower Cable-Stayed Bridge With High Piers

Domestic transport is developing rapidly. Because of the crossing ability, economic, aesthetic and other factors, cable-stayed bridge has been widely used. And multi-tower cable-stayed bridge with high piers has been more applications in some special terrain. The stability is particularly prominent for its own characteristics of multi-tower cable-stayed bridge with high piers. Therefore, it is very necessary that the buckling of multi-tower cable-stayed bridge with high piers is studied.First of all, the development process of multi-tower cable-stayed bridge is introduced in this thesis. And it is indicated that the main problem of multi-tower cable-stayed bridge is buckling of the structure.Secondly, the nonlinear finite element bridge theory and stability theory is briefly descripted according to reference the relevant information. The geometric nonlinearity of struction is considered with the actual situation of the bridge.Thirdly, the Midas/Civil and TDV finite element model of this structure is established, and the first kind buckling problem is calculated and analyzed. The longitudinal buckling of bridge towers is the mode of buckling of the structure in the construction stages. The methods are indicated to improve the stability of the bridge in construction stages, and the results are compared and analyzed. The longitudinal stability of towers is inproved greatly by the way of increasing the longitudinal height of the bridge towers' sections and adding some necessary cables.Finally, the geometric nonlinear buckling problem of the construction stage and the service stage of this bridge is studied.The trend of the critical load factors and linear stability safety factors is consistent in the construction stages. In the same construction stage, the critical load factor is less than the linear stability safety factor. In the service stage of the completed bridge, the critical load factor of full-bridge covered with live load is considered the minimum.And the double nonlinear buckling problem of the construction stage is studied. The critical load factors are less than the geometric nonlinear critical load factors.