The Research On Construction Control Of Flying Swallow X-type CFST Arch Bridge

Since Wangcang East-river bridge was built in1990in Sichuan Province, more and more concrete-filled steel tubular (CFST) arch bridge have been made in recent years. As self-erection structure,The construction process of CFST is complex, the structural system is changing with the construction process. There are many key factors affecting CFST arch bridge construction quality and safety, rate of progress and the economy,such as the selecting of the construction scheme, Steel Tube Concrete Pouring, the construction loading design, Arch Rib Hoisting Method, Construction Stability etc. Based on the third Tuojiang River bridge, this thesis has done some research on some key problems in construction. The main work:(1) The thesis discussed the development survey of CFST arch bridge, common construction method, research status of construction control. The structural features and construction control theory of flying swallow X-type CFST Arch Bridge has been summarized(2) The Side Span’s mechanical behavior of flying swallow X-type CFST Arch Bridge has been Analyzed. The thesis proposes a method which use simplified model to optimize the construction scheme, Optimization content include Steel Tube Concrete Pouring, The construction sequence of beam, tension force of tie bar, and obtains the relevant conclusions and calculation formula. It is discussed that the influence of pile foundation for the structure. The thesis analyze the construction stability and simulation calculation analysis on the construction process, then forecast the reasonable construction of the third Tuojiang River bridge.(3) The setting principle and method of pre-camber of the CFST arch bridge are systematically summed. Based on the third Tuojiang River bridge, the thesis contrast analyze the setting method of pre-camber for the design and construction of the later reference.(4) In-depth study on cable-stayed suspension method of non-bracket cable-stayed suspension supporting method for its widely used in the constructions of CFST arch bridge. The current popular cable force calculation method has been contrast analyzed. The cable force and pre-rigged has been calculated which based on the unknown load factor invariable cable method of Midas Civil, it has been proven to meet the requirements of design, and high precision, no repeated adjusting cable, more convenient. The static structure characteristics and stability during the process of rib hoisting of the third Tuojiang River bridge has been analyzed, and meet the requirements of acceptance of norms.