Internal Force Analysis And Linear Control Of Tied Stacked Arch Bridge

There are variety kinds of structures of oncrete filled steel tubular arch bridge, they have significantly advantages and is applied widely in China. While, as a bold attempt of such structures, tied stacked arch has been successfully put into practice, and it came out that this kind of structure is well designed and is totally competent for the performance we have expected. The upper part of such tied stacked arch structure is composed by double arch ribs both of which bear the weight of bridge deck load. At the same time of making bridges more beautiful, such double-arch also makes the whole structure more stable and finally meets the strict standard of Beijing-Shanghai high-speed rail for linear control.Since90th of last century, concrete filled steel tubular arch bridge is in the ascendant, hundreds kinds of arch bridge had been brought out and applied into engineering practice. However, the tied stacked arch is a brand new structure, the theory and engineering practice is also very new. Its rigorous theoretical study has not started, and there is no uniform criteria list for it.Basic theory of computation and design method of tied stacked arch is initially discussed and summary analyzed in this article. First I simplified the complicated double-arch structure into a much simpler single-arch structure, with the analysis of such simplified single-arch structure I conclude the relationship of the tension of the boom and thrust at springer. Secondly, the internal force which is generated by difference in temperature or shrinkage and creep effects of concrete has been analyzed and the internal force influence lines have been calculated.This Beijing bridge of Beijing-Shanghai high-speed rail studied in this article is located at DIK55+056.3, and it crosses the Guangyang Road of Langfang city. Aimed at meeting the high standard of linear control for high-speed rail, start from analyzing the structure of tied stacked arch, concluded the influnce factors of linear control according to the constrction process. For the purpose of linear control, a pre-camber should be set so that by using a bridge professional software, I selevtively analyzed the deformable features of the critical parts of the bridge during every single construction process, then according to that I brought out relatively accurate and stable pre-camber standard. At last, I contrasted the measured value with the calculated value of the arch rib stress and of the beam deformation, the result is that steel pipe stress is relatively larger but still smaller than calculated value, conclude that the arch rib stress has never exceeded the limits during the construction process. Meanwhile, the shape of the arch rib and the tie tension are both verified.