TABLE OF CONTENTS The formulas and discussion of this section are based on the following assumptions: (1) The column is nominally straight and is subjected only to nominally concentric and axial end loads, and such crookedness and eccentricity as may occur are accidental and not greater than is consistent with standard methods of fabrication and ordinary conditions of service; (2) the column is homogeneous and of uniform cross section; (3) if the column is made up of several longitudinal elements, these elements are so connected as to act integrally; (4) there are no parts so thin as to fail by local buckling before the column as a whole has developed its full strength.
End conditions . The strength of a column is in part dependent on the end conditions, that is, the degree of end fixity or constraint. A column with ends that are supported and fixed, so that there can be neither lateral displacement nor change in slope at either end, is called fixed-ended. A column with ends that are supported against lateral displacement but not constrained against change in slope is called round-ended. A column with one end fixed and the other end neither laterally supported nor otherwise constrained is called free-ended. A column with both end surfaces that are flat and normal to the axis and that bear evenly against rigid loading surfaces is called flat-ended. A column with ends that bear against transverse pins is called pin-ended.
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