Research On Linear Control Technology Of Grand Bridge Over Yangdeng River

In recent years,the state has invested heavily in infrastructure construction.Consequently.the bridge infrastructure has kept pace with road transportation to develop rapidly.Among these,prestress concrete continuous rigid frame bridge,with its peculiar advantages,becomes one of the most competitive bridge types in our country.The technology to build a linear grand bridge is critical and also affected by many factors,such as the structure settlement of continuous girder bridge foundation pier,the elevation of cantilever in the process of cast-in-place construction,the control during closed period,the construction stress of box girder hanging basket cantilever,the deflection monitoring and so on.In order to solve the present construction problems,this paper conducts the research on bridge line control technology in order to promote the development of bridge technology.In this thesis,based on the construction linear technology control during the project of Yangdeng River,analysis is conducted in the following aspects.The first is to analyze the subsidence of bridge pier foundation.The second is to control the vertical casting height of box girder cantilever and to analyze closing stage technique.The third is to monitor stress line load and deflection deformation of bridge structure with a model.In order to ensure the bridge linear,the last is to analyze the error during the whole process as well as draw the following conclusion.Judging from the analysis of measured data on settlement for a long time,it is concluded that the settlement change in two main piers is similar and the limit differential settlement from side piers has great impact on linear control.The elevation of cantilever in the process of cast-in-place construction and the technology control during closed period are the most important and also the most critical part.In order to ensure that the linear state is in conformity with the design,it is a must to control the whole process of bridge construction,to monitor and analyze stress and deflection of cantilever cast-in-place box girder in every phase of beam segment construction with the final purpose for linear bridge.The scheme acts as a reference for the same type of bridge.Geometric control is to control the error accuracy of technology parameters in the whole process of construction,to calculate and analyze measured data from bridge construction,to adjust and determine strictly the rights of observed quantity so that the linear bridge is in accordance with the design.