Research On Stress Control Of Large-span Prestressed Concrete Continuous Girder Bridges

Currently, The prestressed concrete continuous girder bridge is the most widelyused structure in bridge engineering. The cantilever construction method is one of themost commonly used method. The cantilever construction method for large spanprestressed concrete bridge, due to the long construction period and the influence ofvarious uncertain factors during the construction, the actual state of the bridge alwaysdeviates from the theoretical calculation and analysis, leaving the safety hidden trouble,and even may seriously affect the quality of the project construction. In this paper,through comprehensive analysis of the stress monitoring theory and experimental studyon the status quo, using the stress monitoring data of Subei bridge. learning from theexisting research results, studys the stress monitoring of the Prestressed concretecontinuous girder bridge and ensures the state of the construction is still under control.The paper shortly describes the development situation of the stress monitoring onlong-span prestressed concrete continuous girder bridge of domestic and foreign,clarifys the meaning of stress monitoring research. The model is established byDr. bridge and Midas Civil, the datas check each other and validates the accuracy ofthe method of calculation.This paper also simulates the construction condition of Subeibridge in the largest cantilever state to ensure the stability of anchor support. Thecalculation results accord with actual condition, satisfies the requirement of constructionsafety. The sensors in Subei bridge arranged on the specified section are used to get thenormal stress in real-time. This paper uses gray system theory to predict normal stress,By comparing predicted values and the measured values, verify the stress predictions byGM (1,1) metabolism model meets the precision requirement. The prediction providesearly warning of stress. By comparing predicted values and theoretical values, provedthe trend of development trend in conformity with the actual stress. In order to study thetransverse distribution of normal stress with single box double room bridge. The sensorsare embedded in the roof of Z6section28#pier line right chamber and collecte stressvalue in each stage of the whole construction process. Through the analysis find that it’sthe negative shear lag during construction stage and the work has reference value for thefuture.