Abstract:Ultra-long multi-span prestressed continuous girder bridge with good integrity and high driving comfort is increasingly used in engineering projects. However, this kind of bridge is often faced with multiple system transformations in the process of construction. The closure method, time and sequence have a significant influence on the structural mechanical behavior during the construction and completion of the bridge. In view of the closure scheme design of ultra-long multi-span continuous girder bridge, the selection of construction sequence of an ultra-long multi-span prestressed continuous girder bridge with a total length of 864.98 m is studied. By formulating 7 different closure sequences, the finite element is used to simulate and analyze the transformation of load and constraint at each construction stage. The key structural behaviors such as stress, deflection and support displacement of the finished bridge under different closure schemes are analyzed. The advantages and disadvantages of the closure scheme are compared and assessed. The research result shows that the closure sequence "from both sides to the middle" makes the alignment and stress changes of the finished bridge smaller, and is the most reasonable principle for formulating the closure scheme.
