Estimated Length of the Tubular Concrete Columns of High-Rise Buildings

Modern structural solutions for high-rise buildings with reinforced concrete columns generally incorporate rigid joints with monolithic slabs. The column is treated as a compressed rod with end bending moments. The strength of such a column should be calculated for two design sections: the support section (with a large end moment, but ignoring buckling) and in the middle third of the length (with buckling). Bending moments at the mid-height of the column are calculated based on its flexibility and end moments. When determining the design length of the rod, inflection points on its deformation curve should be taken into account. This article derives values for the design length coefficients when only the portion of the column between the inflection points is considered as a post pinned at the ends. Formulas are provided for calculating the design moment at the middle third of the length column depending on the end moments. The proposed calculation method allows for a reduction in the design length of the compressed rod with the adopted connection between the column node and the monolithic slab. Values for effective length coefficient of a standard floor can be set to 0.7. This results in a more theoretically sound solution to the problem of the column strength determining, considering flexibility, which ensures more accurate calculations and often leads to savings in material resources

M.A. ASTAFYEVA¹, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.);
V.I. RIMSHIN^2,3, Doctor of Sciences (Engineering), Professor, Corresponding Member of RAASN (This email address is being protected from spambots. You need JavaScript enabled to view it.);
A.L. KRISHAN¹, Doctor of Sciences (Engineering), Professor, Advisor of RAASN (This email address is being protected from spambots. You need JavaScript enabled to view it.);
M.S. MOROZOV¹, Postgraduate Student (This email address is being protected from spambots. You need JavaScript enabled to view it.)

¹ Magnitogorsk State Technical University named after G.I. Nosov (38, Lenin Avenue, Magnitogorsk, 455000, Russian Federation)
² Scientific-Research Institute of Building Physics of the Russian Academy Architecture and Construction Sciences(21, Lokomotivniy Driveway, Moscow, 127238, Russian Federation)
³ National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)

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