Studies On The Influence To Inner Mechanic And Stability Of Arch Axis Variation Of Concrete-Filled Steel-Tube Arch Bridge With Long-Span

Recent years,with the rapid development of long-span concrete-filled steel tube arch bridge in our coutry, the span of concrete-filled steel tube arch bridge is more and more large ,and so is the control difficult of arch axis .However,till now in our country ,there is no design and construction code for concrete-filled steel-tube arch bridge,specification against arch axis variation is also established on previous bridge-constructing performances.Inevitably,there exist irrational contents for some line shape index mark.It's necessary to analyse the arch axis viriation in construction stage.First,in this thesis, the research present status of domestic and overseas on arch axis variation are roundly introduced,and the thesis takes an inquiry into specification against arch axis variation in the"Standard for quality inspection and assessment of highway engineering"to present the conclusion that some line shape index marks can not satify requirement of the development of long span arch bridge for further perfect.Then ,the thesis adopts the large commercial FEM software ANSYS to establish the space calculation model of MAO CAO JIE bridge.The technique on birth and death of element in ANSYS are applied to simulation analysis in construction stage of concrete-filled steel-tube arch bridge and in construction control calculation from construction stage after steel tube closed.Then ,by theoretical analysis of the influence to inner mechanic and stability of arch axis variation,the thesis thinks that the defect to eveluate and control variation in accordance with design arch axis is indicated ,we suggest that all of these should be done in terms of dead load line.By theoretical analysis ,the calculating method of real bridge dead load line is deduced.After that ,the influence to inner mechnical and stability is calculated in light of some typical arch axis variation.At last,on the basis of MAO CAO JIE concrete-filled steel-tube arch bridge of intermediate bearer of NANXIAN Country in HUNAN Province, the thesis calculates and analyses the influence to inner mechnical and stability of arch axis variation of concrete-filled steel-tube arch bridge with long span.According to theoretical analysis and calculated results ,the author gives some useful suggestion on arch axis variation of concrete-filled steel-tube arch bridge with long-span.