Based on the analysis of the current normative and technical documentation for the design and repair of vertical steel tanks, as well as scientific studies of domestic and foreign authors, were found that at present there is no method that would allow to determine with sufficient accuracy the stress-strain state of a tank that has imperfections geometric form of the wall. Available techniques do not take into account the real rigidity of the metal structure, in particular, the roof, and when setting the boundary conditions, various restrictions are placed on the movement of the upper and lower edges of the wall. In the article, the authors on a real tank have shown that the use of certain design schemes can lead to the occurrence of large errors and, accordingly, to obtain unreliable results. Obviously, such a design scheme cannot be used when choosing real repair technologies. For this purpose, based on the developed finite element model of the RVS-5000 tank with a conical roof, the calculations of the tank withdrawn in repair were carried out in three variants in accordance with the procedure of Transneft PJSC: I - without pinching the upper edge of the wall; II - with pinching of the upper edge of the wall; III - the version proposed by the authors of the article, the most detailed model of metal structures taking into account the real rigidity of the roof. The approach proposed by the authors of the article was developed for the analysis of the stress-strain state of a tank having geometric deviations of the wall shape. Based on the results of the work, it is proposed to supplement the methodology of Appendix A "Method for calculating the stress-strain state of the tank wall during repair by raising the reservoir and replacing the metal wall structures" of the current normative document by requiring mandatory registration of the real rigidity of the entire structure and the roof of the tank when calculating the construction stress-strain state.
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