Effective length of web-tapered pinned I-section column
https://doi.org/10.22227/1997-0935.2026.6.885-897
Abstract
Introduction. This paper presents a comprehensive analytical study of the buckling of I-section columns with web depth varying linearly along the column length. Closed-form solutions were obtained using the analytical Bubnov – Galerkin method and direct integration of the differential equation of the deflected axis for the member. The effectiveness of the Bubnov – Galerkin method is assessed for determining the effective length factor of a pinned centrally compressed column with variable stiffness. An alternative view of the buckling problem for a variable-stiffness column is also proposed, and the solution is supplemented by reconsidering the basis function based on parameter ψ1. This approach provides an independent analysis of the buckling problem of I-section columns with a tapered web. The obtained values of the effective length factor are close to each other, and the mean relative error does not exceed 5 %.
Materials and methods. The analytical Bubnov – Galerkin method and direct integration of the differential equation were used.
Results. Using analytical methods, closed-form equations for the effective length factor of an I-section column with variable stiffness were obtained. In total, three calculation formulas are presented.
Conclusions. The proposed formulas for the effective length factor make it possible to perform a stability calculation of a pinned I-section column with linearly varying web depth along its length. The study also provides additional information on eccentrically loaded I-section members with a tapered web.
About the Author
A. O. Ilyushenkov
Territorial Design Institute “Khabarovskpromproekt”
Russian Federation
Russian Federation
Alexander O. Ilyushenkov — industrial and civil construction engineer, leading engineer of the Architectural and Construction Department
2 Ussuriysky boulevard, Khabarovsk, 680000
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Review
For citations:
Ilyushenkov A.O. Effective length of web-tapered pinned I-section column. Vestnik MGSU. 2026;21(6):885-897. (In Russ.) https://doi.org/10.22227/1997-0935.2026.6.885-897
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