Research On Construction Control Of New Jinggang Bridge Tower

The cable-stayed bridge develops rapidly in China.Compared with other types of bridges,the shape of the cable-stayed bridge is beautiful and the overall structure is reasonable.It can be designed as a long-span bridge with a main span of 100 meters or more kilometers,and becomes one of the most competitive bridge types in modern bridge engineering.The research background is that the new Jinggangshan Bridge is a single tower cable-stayed bridge,while the single pylon cable-stayed bridge occupies15%-25% in the whole cable-stayed bridge.Cable tower is a part of single tower cable-stayed bridge.It is an important load-bearing structure of cable-stayed bridge with single tower.The upper part of the cable stayed bridge is passed through the cable tower to the foundation.Therefore,based on the new Jinggangshan bridge single tower cable-stayed bridge-diamond shaped tower as an example,based on theoretical analysis,establish were analyzed to provide reference data to control tower structure construction.Considering the effect of wind load,temperature load and concrete shrinkage and creep,the stress and deformation trend of pylon structure are analyzed.Through detailed reading of existing literature and research results,this paper briefly introduces the development history of cable-stayed bridge in the world and the history of cable-stayed bridge in China.On this basis,it introduces the common structural form and stress condition of cable tower of cable stayed bridge.Overview of construction control theory of 2 single pylon cable stayed bridge.First of all,the general idea of the construction control theory of cable stayed bridge pylon is expounded.Secondly,the construction control methods are introduced,including the formal calculation method,the inversion calculation method,the inverted positive iteration method and the free stress calculation method.Based on the actual situation of the project,the calculated results are in good agreement with the actual situation.Establish the diamond shape cable tower model of new Jinggangshan Bridge.According to the whole process of tower construction,consider the influence of wind load,temperature and concrete shrinkage and creep on the cable tower,and calculate the stability of the pylon,bare tower,the largest cantilever stage and the completion stage.For the construction of the key issues,focus on the analysis of the temporary support(pull)segment of rod and the calculation of the tower in the typical construction process of tower stress.In the maximum cantilever stage and construction stage,the stress of the pylon is checked,and the tower top displacement at the construction stage is obtained.Sensitivity analysis of the design parameters that affect the stress and deformation of the pylon,including stiffness,weight and temperature,is introduced.The method of parameter identification is introduced.