Buckling Analysis of Tapered Continuous Columns by Using Modified Buckling Mode Shapes

Abstract

Elastic critical buckling load of a column depends on various parameters, such as boundary conditions, material, and cross-section geometry. The main purpose of this work is to present a new method for investigating the buckling load of tapered columns subjected to axial force. The proposed method is based on modified buckling mode shape of tapered structure and perturbation theory. The mode shape of the damaged structure can be expressed as a linear combination of mode shapes of the intact structure. Variations in length in piecewise form can be positive or negative. The method can be used for single-span and continuous columns. Comparison of results with those of finite element and Timoshenko methods shows the high accuracy and efficiency of the proposed method for detecting buckling load.

Keywords

Buckling analysis / Tapered column / Continuous columns / Finite element method / Modified buckling mode shapes

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