Narrow Results

This paper applies the energy limit concept to the stability problem of structures and structural systems. New concepts such as, the energy capacity that measures accumulated energy in the structure before failure and virtual large displacements that lead to significant plastic deformations are introduced and defined. Proposed theory considers full load cycle, from the initiation of the instability until complete collapse of the structure. New equations for the determination of critical loads are derived, presented, and compared to known results. Proposed new equations take into consideration simultaneous effects of axial, bending, shear and torque deformations. The results of the study are substantiated by comparison with examples with known answers.