Research On Unloading Analysis Of The Temporary Support In A Steel Structure With Special-shaped Space Surface

Large span spatial structure has been widely used due to its rich architectural modelling and flexible space layout, and can fully meet the characteristics of public buildings in the functional, aesthetic, space requirements. The construction process of special shaped space steel structure is complex, and the construction cost is high. Force state of the main structure under design condition and the structure in the construction process are very different. In order to facilitate the construction of the main structure, the temporary support system should be set up in the construction process. The temporary support should be unloaded when the installation of the main structure has been completed. How to make the structure smooth from the stress state of the construction to the design stress state is one of the key links in the whole construction process.The main research contents of this paper are as follows:(1) This paper has summarized the common installation methods and temporary support systems in spatial steel structure construction; analyzed the application and problems which need to be paid attention in engineering about different installation and temporary support system; simply summarized the theoretical foundation on simulation analysis of construction and calculation method; analyzed the applicability of different typical displacement-control methods.(2) Taking a velarium system of steel structure with special-shaped space surface as an example, the unloading analysis model is established by using finite element analysis software MIDAS / Gen. The proposed different unloading plans used in actual project aresimulated, compared with the stress, deformation and temporary support of the main structure under different schemes, to determine the optimal unloading construction scheme.(3) According to the characteristics of the engineering structure,analysis on the effect of unloading temporary supports in advanced on construction. Based on the different structure installation order, two plans for unloading temporary support in advance are proposed. The calculation results of internal force, deformation and support force of the structure under different advance unloading schemes are presented, and compared with the results from unloading in advance with normal unloading, to demonstrate the feasibility of unloading the temporary support system in advance.The above analysis and research provide a reference for the selection of related construction schemes of similar space steel structure.