High Pier Span Continuous Rigid Frame Curved Bridge Stability Of The Whole Process Of Analysis

The research in this paper is an important part of the stability analysis in the whole stage of large-span curved bridges with high piers which is a sub project of the national transportation scientifical project in western regions, the research of the design and construction technology of large-span curved bridges with high piers. In this paper, The purpose is to seek the stability sensitive parameters and the inner rules of straight and curved lone span continuous rigid-frame bridge with high piers which are applied for production through plentiful numerical tests to plenty of large-span continuous rigid-frame bridge with high piers.Besed on analysing the development and nowadays conditions of stability theory in and abroad, this paper points out that the stability is as significant as intensity to bridges large-span bridges with high piers. Consequently, the main goal of this paper is fetched out. Two kinds of stability problems are simply introduced and it points out that most stability problems come up against in practice is the second stability problem. Furthermore, we come to the conclusion that only if with the study to the relation of geometrical nonlinear to material nonlinear of structure can we deeply discover the essential of complicated stability problems. The formula deducted by energy theory which approximatively resolving critical load of self-stability and stability in cantilever construction of high pier with uniform section, and especially the approximate formulae of critical load of self-stability and stability in cantilever construction of high pier of curved bridge are deducted in detail. The deduction is briefly and prone to be operated. The way, the solution and the basic steps solving the stability of large-span continuous rigid-frame bridge with high piers using finite element are given. BridgeB-W, a self-write special bridge program, is validated by examples. The result is compared with ANSYS, a large current calculation program, to make clear that the result by BridgeB-W is exact and the precision satisfy the need of engineering. The stability of several large-span continuous rigid-frame bridges with high piers are calculated and analysed by ANSYS and BridgeB-W. As a result, the inner rules influencing the stability of large-span continuous rigid-frame bridge withhigh piers are initially brought forward, that is, the stability of curved bridge is not as good as straight bridge on the stage of the most cantilever cast, while the thing is reversed when a whole bridge is completed; to double thin-wall pier, it's good to set one tie girder at the spot of the half of a pier while it's good to set two tie girders near the spot of the half of a pier; in view of the effect of nonlinear, it come to the conclusion that the stability of curved continuous rigid-frame bridge translates into the problem of limit load considering material maximum intensity, etc. The conclusion can provide reference to the design and construction of the same type, and also lay a foundation for the further study.