The Study On Prestressed System And Stress Anastomotisis Analysis Of Wide Box Girder

In recent years, ordinary box girder bridge has been difficult to meet traffic demand due torapid economic development and the increase of traffic pressure, especially some big cities.The rising of singles bridge width can adapt to the development of modern transportation,many wide box sections, which are big cantilever, single box, multi-room, appeared in theprojects of prestressed concrete bridge at home and abroad. The wide box bridge has thefollowing properties: the ratio of wide-span of box girder is more than or equal to1:2,transverse flange is wide, box wall is thin, web spacing is far and so on.At first, shear lag phenomenon, space stress state, prestressed steel beam layout,construction and settings of wide box girder are introduced in this study. The meaning ofintensive study of wide box girder is put forward, the reserch may provide theoreticalfoundation for the building of reasonable prestressed system and the anastomotisis analysisbetween box girder prestress and load of wide box girder.Based on a box girder bridge, which is continuous, three span, prestressed concrete, theresearch analyses and calculates wide box girder by structure mechanics analysis, and solvesthe difference between box girder and wide box girder by analytical method. The space modelof the wide box girder is built by ANSYS, spatial mechanical performance is analyzed andcompared with both of the results of the plexiglass model and the analytic method. Thesensitivity stress analysis is processed by the size conversion of roof and web of box widegirder section in order to find a rational section form of wide box girder.The effect of thestructure three-dimensional prestress of wide box girder is researched, meamwhile, the effectof different reinforcement and bar spacing on the mechanical performance of wide box girderis analyzed. At the last, a rational prestress system is explored based on stress anastomosis ofwide box girder.The reseach suggests the space stress performance, rational section form, prestressedconfiguration and anastomosis analysis of wide girders of single box and multi-room from theabove analysis results, the reseach result can provide some extent reference value, makeprestressed configuration economic rationality, reduce the harm caused by prestressedconfiguration and is help for the analysis of prestressed system and anastomosis of wide boxgirder bridge.