Stability Analysis Of Long-span Curve Rigid Frame Bridge With High Piers In Whole Stage

The research in this paper is an important part of the stability analysis in the whole stage of long-span curved bridges with high piers which is a sub-project of the national transportation scientific project in western regions, which is the research of the design and construction technology of long-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 long-span continuous rigid-frame bridge with high piers which are applied for production through plentiful numerical tests to plenty of long-span continuous rigid-frame bridge with high piers.Based on analyzing the development and nowadays conditions of stability theory in and abroad, this paper points out that the stability is as significant as intensity to long-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 through studying the geometrical nonlinearity and material nonlinearity of structure the stability problems can be deeply discovered. The formula deducted by energy theory which approximately resolving critical load of self-stability and structure stability in cantilever construction of high pier with uniform section, and especially the approximate formulae of critical load of self-stability and structure 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 of the stability for long-span continuous rigid-frame bridge with high piers using finite element are given. Bridge B-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 Bridge B-W is exact and the precision satisfy the need of civil engineering. The stability of several large-span continuous rigid-frame bridges with high piers is calculated and analyzed by ANSYS and Bridge B-W. As a result, the inner rules influencing the stability of long-span continuous rigid-frame bridge with high 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...