Research On Stability In Constructing Process Of Long-span Steel Box Basket-handling Arch Bridge

With the increase of the span of the arch bridge,the stability problem become more and more evidence and become one of the most important control factor of arch bridge design. This paper bases on Chaoyang reconstruction bridge in Chongqing, through processing stability analysis, and discusses stability coefficients in all the constructing process and provides profitable suggestion for design of the same kind of bridge.The existing theory is my paper's guidance, I use finite element method, anglicizing the linear and geometrical nonlinear influence on stability of arch bridge in constructing process .The result of the calculation indicates that Steel box arch rib cross-sectional stiffness of a larger, when the provision of adequate wind bracing, arch bridge the plane-outer stability above plane-inner and plane-inner will play a controlling role in the constructing process. Using shell element simulation of the working conditions and the conditions closer to actual construction, which more accurately obtain the actual bridge stability factor. At the same time we can see that based on the geometric nonlinear stability factor under elastic analysis, and therefore in the bridge design should ensure that a high linear elastic stability factor to the stability of sufficient reserves. Taking a rib segment to do local buckling analysis, according to structural stability theory, elements of local instability may lead to instability of the structure as a whole, but not necessarily a result, because the board after the pieces of local instability occurs stress re-distribution, but the construction should also be taken seriously enough.