A structural member loaded axially in compression is generally called a compression member. Vertical compression members in buildings are called columns, posts or stanchions. A compression member in roof trusses is called struts and in a crane is called a boom. If the load on a column is applied through the center of gravity of its cross section, it is called an 'axial load' . A load at any other point in the cross section is known as an eccentric load. As the axial load on a perfectly straight slender column with elastic material properties is increased in magnitude, this ideal column passes through three states: a)Stable equilibrium : The straight column under load is in stable equilibrium if a lateral force, applied between the two ends of the column, produces a small lateral deflection which disappears and the column returns to its straight form when the lateral force is removed. b)Neutral equilibrium : If the colum...
Lecture Notes