The Research Of The Precast Concrete Beams Hoisting Method In The Large Arch Bridge

With Chinese rapid development of highway traffic construction, steel-concrete compositetheoretical studies structures are also increasingly sophisticated. Arch Bridge as a new bridge, because of its unique characteristics and the advantages of force and simple construction erection, as well as the development and application of high-strength materials, this type of bridge has been widely sprung up in China.However, China has a huge number of under constructing and constructed CFST arch bridges, but the corresponding design specification is failed to be promulgated. In addition, its main arch steel erection process has a relatively mature construction methods in the process of construction, in current universal designing for the first pre-stressed beams, and then laying plates carry away bridge deck system this suspension system construction method is adapted to local conditions. However, its limitations can not be ignored. In this paper, Setting Sichuan Qu County Drainage River Bridge main span of206m asuka CFST as an engineering example, under the existing construction machinery and equipment and construction materials,taking into account a variety of factors influence, rational use of the cable crane with Bailey truss assembly composed of hoisting system,just used13days to put25piece of pre-stressed precast concrete beams successful hoisting which has length of26.78m weighing900kN. In this paper, its simulation has been analyzed through the collection of relevant information as well as the process of establishing lifting gantry tower with Bailey truss construction in the most unfavorable conditions of the calculation model. Calculate the lifting gantry tower system deviation, the bottom most unfavorable strength of the force rod, the stability of the tower, Bailey truss stiffness, strength, and chord structure if it is reasonable. The structural optimization is analyzed through simulation and measured values compared to the safety of lifting method, rationality and an analytical summary of the advantages and disadvantages. Analysis show that:the initial tension of the cable through the air control tower door style previously applied to offset the expected deviation tower displacement of the lifting process is effective and feasible, lifting the overall stress level during the low tower, good stability, has a high safety reserves; additionally, Bailey truss assembly lifting process in each chord stress levels low, reasonable structure, but a large scratch across the middle and lower, showing the overall stiffness is insufficient.By improving the optimization design, Bailey trusses overall stiffness and local stability is enhanced chord stress levels are effectively reduced.Through this analysis, this cable crane gantry tower truss assembly with Bailey combined method is used for lifting heavy lifting is safe, reasonable and feasible. And with the construction of high efficiency, less capital investment and so on. The bridge takes full advantage of the main arch previously used crane hoisting ropes and the original cast concrete arch transom bracket side of Bailey. Thus, this benefits to avoiding the erection of temporary support, leasing large floating cranes, bridges and other machinery and equipment costs. Lastly, this paper will provide a better method to construct the bridge of heavy lifting precast beam,also valuable reference for relevant information will be given to support the basis for engineering applications.