Analysis Of Several Problems In Construction Control Of High Pier Continuous Rigid Frame Bridge

With the deepening of reform and opening up,China's economy has developed rapidly and the requirements for infrastructure construction have been gradually raised.This paper takes a high-pier continuous rigid frame bridge on Yibi Expressway as the research object,mainly analyzing some problems in the construction control process of the bridge:(1)Based on the bridge construction control system and combined with the on-site construction process,the content of bridge construction monitoring,construction control method,construction analysis method and construction control calculation are determined.(2)Establish the calculation model of the bridge according to the construction process and combining with the finite element software,provide the theoretical values under ideal state for each construction stage,compare with the measured values in the construction control process,and establish the cyclic and repetitive process of forecasting,measuring,discriminating,correcting and forecasting,so as to ensure that the geometric linearity and stress state of the structure under the completed state meet the design requirements.(3)Referring to domestic rigid frame bridges built and operated in China and combining with finite element software,analyze the factors affecting the amount of jacking displacement,determine the amount of horizontal displacement and jacking thrust,simulate the state after 5years of completion of the bridge,and compare and analyze the internal force of pier section and deflection changes of beam.(4)Basic calculation theory of bridge stability analysis is studied,self-stability formula of high pier is analyzed by theoretical formula and compared with the result of finite element calculation model.The finite element model is used to analyze the construction stability at the stage of maximum cantilever state,and the buckling characteristics and modes under different load combinations under different conditions are obtained.Meanwhile,for the maximum cantilever state under the most unfavorable load combination,the parameters of pier concrete strength,hollow pier wall thickNess,diaphragm position and diaphragm thickNess are analyzed.Meanwhile,the moving live load of the vehicle is transformed into static load.Force loads are compared and analyzed for the stability of the bridge during operation.