Study On The Construction Control And Risk Assessment Of T-Shaped Rigid Frame Bridge Under Level Rotation

The method of T-shape rotation rigid frame bridge construction developed in recent years,a new bridge structure and effective construction method which across the railway, deep valleys,rapids,roads and other special conditions.The level rotation construction method technical is difficulty and high accuracy,and includeing uncertainty and certainty factors.In order to ensure the overpass bridge high quality and safety,it is necessary to control the construction process and the research on risk assessment.The paper based on the project of construction control of Binzhou to Dezhou(border of Shandong and Hebei) highway overpass across the Beijing-ShangHai railway.And then in order to provide the theory track about of the construction control,it has analysed the whole bridge construction process of the simulation in the use of two different kinds of finite element analysis softwares-Doctor Bridge and Midas/Civil;the linear forecasting,controlling and adjusting of the girder,the measurement and controls of the section stress on the level rotation,the weighing test and the other key controlled technologies.The results show that:the controls about the installation precision of the level rotating system is the key task of the level rotation;and this paper proposed a method of the linear adjusting that based on the least square method,which can reduce the bad influence of construction error and the optimum adjustment;meanwhile,comparing the two kind methods of displacement measurement about the weighing test we'll known that it can eliminate effect of vertical deformation of butter layer,and the displacement mutations are more apparent,the critical force is much easy and accurate to verdict.According to the risk assessment and management theory, using the Goal Decomposition+Operation-Risk Decomposition+Comprehensive recognition method of investigation from experts,and then it has identified the risk factors of the level rotation,and assessed the main risk resource of the rotating system on the method of combined with the ALARP risk evaluation matrix and the single factor analysis,and put forward the countermeasures on risk resource about the level rotation construction of T-shaped rigid frame bridge and providing the reference of similar level rotation construction risk assessment.