Stability Analysis Of Long-Span Concrete Arch Bridge With Stiff Skeleton

The concrete arch bridge with stiff skeleton is the typical application of steel reinforced concrete (SRC) in the bridge engineering. The stiff skeleton can support the concrete casting load as construction frame and as an integral part of the section of arch rib, there is no necessary to remove it when bridge completed, that greatly reduces the construction difficulty of long span concrete arch bridge. To long-span concrete arch bridge with stiff skeleton, their stability problem is outstanding, especially in construction stage, and that generally become a major factor in the design and construction of long-span SRC arch bridge. Based on the summary of current researches, this thesis used analytical method to study the influence of main parameters of structure on the lateral stability of arch ribs and applied finite element method to research on the self-stability and stability in construction stage of SRC concrete arch bridge. The main research work covers the following aspects:1. This thesis summarized the development history and presented situation of SRC structure; generally introduced the applications of SRC structure in bridge engineering; overviewed the analytical method and finite element method of stability analysis of arch ribs and pointed out the importance to analyze stability of SRC arch bridge in the construction stage.2. This thesis introduced the vertical stability critical load calculation formula of common arch ribs; with energy method to deduce the lateral stability critical load calculation formula of circular double arches which subjected to orientedly conservative loadings and non-orientedly conservative loadings. And used the formula to analyze the influence of main parameters of structure on the lateral stability of ribs.3. Referring to ANSYS software, this thesis created a dimensional computing modal of the Jialing River Super-major Bridge in Zhaohua,Sichuan; analyzed the main construction stage stability of SRC arch bridge considering the influence of material nonlinearity, geometry nonlinearity and double nonlinearity.4. Taken the Jialing River Super-major Bridge in Zhaohua,Sichuan for instance, this thesis used Midas Civil software to analyze the influence of main parameters of concrete arch bridge on stability of SRC arch ribs and bridge.Based on the researches mentioned above, some useful conclusions were generalized, that has some referential value for the design and construction of SRC arch bridge.