What is Column?
A column is a line element (long slender bar) subjected to axial compression. The term is frequently used to describe a vertical member.Structural members (i.e., columns) are generally stable when subjected to tensile loading and fail when the stress in the cross section exceeds the ultimate strength of material.
In case of elements (i.e., column) subjected to the compressive loading, secondary bending effect e.g., imperfections within material and/or fabrication process, inaccurate positioning of loads or asymmetry of cross section can induce premature failure either in part of cross section or of the whole element. In such case failure mode is normally the Buckling.
Types of Buckling:
Buckling is categorized into the following:
Lateral Torsional buckling
The design of the most of the compressive members is governed by over-all buckling capacity. i.e., the maximum compressive load which can be carried before the failure occurs due to the excessive deflection in the plane of greatest slenderness ratio.
Typical overall buckling occur in columns of frame structure and in compression members of trusses.
Types of Column:
The column which has a relatively low slenderness ratio is called the short column (e.g., length of member is not greater than the 10 time to the least cross sectional dimension).
Failure occur when stress over the cross section reaches the yield or crushing value of the material.Such element fail by crushing of material induced by predominantly axial compressive stress (flexure stresses are not dominant).
Slender Column:The column which has a relatively high slenderness ratio is called the slender or long column (e.g., length is greater than the 30 time to the least cross sectional dimension).Such element fail due to excessive lateral deflection (i.e., buckling) at a value of stress considerably less than the yield or crushing value.In slender column flexure stress are dominant and compressive stress are not too important.
The failure of columns is neither short nor slender and occur due the combination buckling and yielding/crushing.
Your description is have extreme level of knowledge regarding column. Its related to column their behaviour, what kind of failures etc. But your content is not related to your question.
Simply column is a vertical or we can say that axial member or element of the buildings.
While we designing a column nom of things we consider in this whole process.
We our engineers we should give answers to the point our work is to simplify the work not to complex it.
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