Allowable Axial Stresses in Segmented Columns

An axially loaded column which is stepped, or one for which axial loads and/or reactions are applied at points other than its ends, may be referred to as a segmented column. Each segment of such a column has constant properties and constant load along its length. Crane columns and pipe supports are typical examples. Frequently such columns have eccentric or lateral loads which also produce bending, but for determining allowable axial stresses the columns may be reduced to forms. For elastic behavior, the critical condition in a segmented column with a given combination of proportional loads usually depends upon a complex interaction between the segments such that the whole column may be regarded as buckled. The contribution of each segment is a function of its properties, its load, and the position of the segment along the length of the column. The critical condition for an individual segment is generally unknown, because each segment relies on the other segments for its end conditions.