Analysis On The Large Span Conctere-filled Steel Tube Arch Aqueduct In Shanxi Province

As a kind of composite material model of concrete filled steel tube,conctere-filled steel tube has the advantages of high bearing capacity, good plastic and toughness, high economic benefit and the construction is simple, widely used in high-rise buildings and the field of highway bridges, but rarely used in hydro project. In view of the aqueduct and the bridge is similar, the author thinks that in the structure, we can refer to some concrete filled steel tubular arch bridge theory experience,combined with the structure characteristics of the development of a new aqueduct and concrete filled steel tube arch aqueduct.Based on this we can conduct further analysis.This paper take the Shanxi irrigation project design as background, according to the structural characteristics of concrete filled steel tube arch bridge and aqueduct,use midas conduct design and analysis. The analysis aims to the static and dynamic characteristics of the theory, for the future of their development to provide certain theoretical basis, so as to promote the application and development of the new type of aqueduct. The main research contents of this paper are as follows:1. Study are on the determination of the concrete-filled steel tube arch aqueduct structure of different span. By analyzing the structure characteristics of concrete filled steel tubular arch structure and aqueduct, structural type of every span of structure and layout of each component and the section dimensions were determined.2. On the modal analysis, we obtain the main vibration of the three structure:in-plane vibration, out-plane vibration and partly vibration,some components with torsion. At the same time, compared the vibration frequency with their own pure steel structure,we can obtain the effect of rigidity on natural vibration frequency of structure.3. Using finite element analysis software Midas, set up finite element models of different span, analysis under different working conditions, the displacement across the deformation of the structure and the structure stress performance, and analyzed with the increase of span changes of each index structure.4. Launch seismic response spectrum method and elastic time-history on every model.Using the above two methods,develop one-way seismic action and composite seismic action.Get response of displacement and internal force of key parts of the structure in various seismic condition,and conduct further analysis.we can get that the transverse seismic action is more sensitive and the vertical seismic action is less sensitive. The difference of displacement response of the structure between one-way seismic and bidirectional seismic loads is not big, but it has obvious increase in internal force. Through the contrast analysis shows that, with the increase of span, the out-of-plane bending moment of arch rib is greater, the seismic effect of the structure of the more obvious.5. In the earthquake, the key part of the structure stress is less than proportional limit of each span steel pipe concrete structure, indicating the cross structure in the elastic stage, is safe.