Construction Control Of Long-Span Prestressed Concrete Continuous Rigid-Frame Bridges With High Pier

With the development and application of new technology, new equipment, new materials and new design means, the prestressed concrete continuous rigid frame bridge is widely used because of its convenient and fast construction, lightful line type, and long-span ability.The long-span prestressed concrete continuous rigid frame bridge construction methods commonly used balanced cantilever casting method. Making process among the cantilever construction, the structure is bound to be many factors affect it, such as the control error, error parameters exist in the presence of construction, the measurement error as well as the presence of creep of concrete shrinkage, temperature variations and the like. During the construction phase of the bridge with the changing structure and the load state of the internal forces and deformation of the structure will follow constantly changing, and the change produced by a relatively large margin. To ensure the construction quality and safety during bridge construction, the structure must bridge internal force distribution and a linear bridge monitor, which is the bridge construction control content.This text combines the project practice of the TianQiao Bridge, has studied the key technical issues of continuous rigid frame bridge construction. Taking into account the bearing platform concrete of bridge is massive concrete, so this text has studied the problems to control massive concrete hydration heat temperature, to explore the feasibility of the bearing platform cooling system layout.This article focused on the bridge during cantilever construction linear control and stress control study, the construction of the concrete application of control theory to engineering practice are analyzed, while using the bridge structure analysis software MIDAS /CIVIL paragraph by paragraph on a full-bridge construction simulation analysis as the construction phase adjustment control basis. Numerical analysis results determined to bridge camber and camber construction, finally got a total of precamber theoretical value determined formula formwork elevation, by comparison with the actual monitoring results illustrate the calculation results correct. Stress control, software analysis and calculation from the obtained theoretical stress value of each construction phase structure, by comparison with the actual monitoring results are basically consistent, reaching the goal of the bridge stress control.