The Analysis And Study Of The Stability On The LiangShuiHe Long-Span Bridge

As the rapid development of the social economy, the bridge constructions will step in a new developed level. Lightweight, long-span, new face bridge will have a chance to develop. How to make a originality innovation by proper design is a great challenge for engineering designers.Relating to the Lightweight, long-span, new face bridge structures, stability problem can not be ignored. In some large-scale project item, that may be a more important problem. To the large-scale bridge structure, how to properly solve the stability problem with the construction stage and operation stage after the bridge finished, that is a key problem on the bridge's safety operation.Liangshuihe long-span bridge is taking the through tied arch bridge of preliminary design scheme, it is the only one which can be designed to be a long-span bridge, to some extent, the meaning is more important. The cross bracings of that bridge break through the conventional concept, not only take the action by connecting the two arch ribs ,but also carry the load transferred by the middle suspender. The middle suspenders solve the problem induced by broad deck, at the meantime the cross bracing's stability also induced to the design. How to properly solve the cross bracing's stability, and meanwhile take the esthetics into account, that is a problem needs to be further analyzes and studies on.This text is taking the Liangshuihe preliminary design scheme as a blueprint, and discusses the effects of the cross bracing's structural form and element type which to choose on stability. At the same time, this text also computes the bridge's stability on different work conditions with the optimum cross bracings. During the computation of the liangshuihe long-span bridge's stability, two methods was used to compute the stability: the Eigenvalue Buckling analysis and the Nonlinear Stability analysis involving tracing the load-deflection path and finding the corresponding collapse load, and compared the results of the two methods. By comparing the analysis's results, the Nonlinear Stability analysis's safety coefficient does not reach half of the Eigenvalue Buckling analysis's safety coefficient. That means in the actual project, the influence of the material nonlinear and the geometric nonlinear etc are great. In order to ensure the safety of the large-scale structure, inducing the influence of the material nonlinear and the geometric nonlinear etc to the stability of the structure is necessary.