ABSTRACT
The availability of electronic computers permits the use of more accurate methods in analyzing structures. Moreover, recent advances in manufacturing resulted in stronger engineering materials whose actual strength varies little from that specified by the manufacturer. These developments led to the reduction of the factors of safety used in the design of structures and the concomitant decrease of the area of the cross sections of their members. However, members of thin cross sections may reach a state of unstable equilibrium and fail by buckling at loads less than those which initiate yielding of one or more of their particles.
