Study And Application Of Fabricating And Lifting Segment By Segment Technology For Large Span Steel Box Beam

In order to meet the challenge of usage and load-supporting, long span steel box beam is extensively used in the field of bridge engineerings. However, steel box beam is used in few building engineerings,but space structures such as gird structure, stereo truss and so on. Compare with long span steel bridges, steel structures of building engineerings have features as more flexibilitier and more strict installation accuracy, structure deformation control is more important. It's uneconomic that solid web girds are used in long span structures, but have merits as favorable cross-section nature, favorable load-supporting capability and smooth appearance.If thickness of slab reduced, structure rationally optimized, steel box beam can possess preferable economization, and expand its building field of application further. Fabrication and lifting segment by segment technology for is regarded as the study object of the text. Based on the above condition, study counter-arhed values determination, methods of fabrication and installation, designation and installation of falseworks, technologies of lifting segment by segment and deformation control, technologies of localization and measurement.Besides, illustrating Shenzhen conference and exhibition center, expatiates fabrication and lifting process of long span steel box beam. The main research contents are as follows: 1, Counter-arhed values determination of box beam Discuss the variation of stress and deformation of structure with falsework or no by structural analysis, which can be base of structure construction. Before install long span box beam segment by segment, lofting state should be determined, by this mean, structure can restitute initial state. Therefore, the paper expatiates counter-arched method of long span box beam-iteration, and the process of counter-arched calculation of Shenzhen conference and exhibition center. 2, Fabrication and installation methods of box beam Regard fabrication process of box beam as main route, fabrication technology of plates, assembly technology, welding technology, and integral consolidation technology are depicted in the paper. Futhermore, various install methods are generalized in the paper. 3, Falsework designation and installation the constitution designation methods, strength and stability calculation methods, behaviour analysis methods, and fabrication and installation technology are expatiated in the paper. 4, Technologies of lifting segment by segment and deformation control of box beam Segments division, transportation and stacking of components, consolidation of components, lifting of components, field welding, and control means in the process of box beam release are particularly depicted in the paper. 5, Location and measuring technologies in process of box beam installation It is particularly depicted in the paper that global and local detail measuring methods of engeering, and methods of structure deformation monitor and stress monitor. 6, Case study On the basis of above basic theory, fabrication and installation technologies of long span box beam in Shenzhen Conference and exhibition center is discussed, and solving methods of several technical difficulties are also introduced. Objecting summarizing fabrication and installation of long span box beam, summarizing the couter-arch method, fabrication technology, lifting-segment-by –segment technology, and deformation control measures, bring forward the importance of ribbed stiffener to box beam, variation of stress and deformation of structure after falseworks are striked,behaviour analysis method of falsework. It is practical valuable to promote the theorization and generalization of fabrication and installation technologies of long span box beam.