Study And Application Of Lifting Segment By Segment Technology For Large Span Steel Grid-frame

At present, large span steel grid-frame structure is used more continually the one of the large span space structures. Its design theory becomes more and more ripe, but the construction method still remains to be perfect. During the structure develops several decades, the lifting technology segment by segment for large span steel grid-frame constant to raise. Meanwhile, the model of the structure is more peculiar, and its span is larger. So need to the technology contain the systematization by stage even more, and demand to construction have enough securities too. If the grid-frame structure lifted segment by segment, its structure segments afford different force with different operating modes. In order to the security of lifting construction, the quality of hoisting and the stability of the structure, it is necessary to strengthen the security analysis of the grid-frame construction.During the construction of large span steel grid-frame structure, construction organizations estimated mostly the security of lifting by experience, and had hardly whole and systematical analysis, so it brings the non-safety factor to structures construction.Lifting segment by segment technology for large span steel grid-frame is regarded as the study object of the text. Based on the above condition, study the establishment of the project, the security analysis of several operating modes and the construction of the technology. And the security analysis is the finite method which is the space grid-frame method for analyzing falseworks and the space truss method for analyzing grid segment.The main research contents are as follows,1, Make the scheme lifting segment by segmentTo the grid-frame structure lifted segment by segment, the work must be done are selecting machinery of hoisting, compartmentalizing lifting segment of grid-frame, choosing temporary supports, designing patching supports and assembling structure element etc, which is able to ensure quality and safety of construction.2, Analyze the security of lifting modesUsing ANSYS and analyzing in detail the security of the construction under kinds of lifting conditions. Analysis emphases of operating modes are the deformation and internal forces of temporary supports and structure segments in lifting, after lifting andafter removing supports.3, Construct the grid-frame by lifting segment by segmentThis part successively summarized the methods of hoisting temporary supports and structure segments, the methods of constructing inlaid and mended segments and the method of removing temporary supports. Moreover, the reasons of many kinds of construction question have also analyzed and the measure has been proposed.4, Discuss the background of the projectCombined the latticed shell of the stadium in Chongqing Olympic Sports Centre, the security of the structure elements lifted segment by segment is discussed, and the technological difficulty of project is analyzed, such as compartmentalizing grid-frame segment.On the basis of the lifting-segment-by-segment techniques for large span steel grid-frame structure, summarizing the construction method and principle of the technology and the analysis method of operating modes are going to be helpful to promote the lifting-segment-by-segment techniques for large span steel grid-frame structure to be perfected and improve the research and engineering practice in theory. And, it is theoretical that the certain search for designing and constructing of large span steel grid-frame structural.