The subject of this book is the stability of structures subjected to external loading that induces compressive stresses in the body of the structures. The structural elements examined are beams, columns, beam-columns, frames, rectangular plates, circular plates, cylindrical shells, and general shells. Emphasis is on understanding the behavior of structures in terms of load displacement
characteristics; on formulation of the governing equations; and on calculation of the critical load.
Buckling is essentially flexural behavior. Therefore, it is imperative to examine the condition of equilibrium in a flexurally deformed configuration (adjacent equilibrium position). The governing stability equations are derived by both the equilibrium method and the energy method based on the calculus of variations invoking the Trefftz criterion.
The book has been planned for a two-semester course. The first chapter introduces the buckling of columns. It begins with the linear elastic theory and proceeds to include the effects of large deformations and inelastic behavior.
In Chapter 2 various approximate methods are illustrated along with the fundamentals of energy methods. The chapter concludes by introducing several special topics, some of them advanced, that are useful in understanding the physical resistance mechanisms and consistent and rigorous mathematical analysis.
Chapters 3 and 4 cover buckling of beamcolumns.
Chapter 5 presents torsion in structures in some detail, which is one of the least-well-understood subjects in the entire spectrum of structural mechanics. Strictly speaking, torsion itself does not belong to a work on structural stability, but it needs to be covered to some extent if one is to have a better understanding of buckling accompanied with torsional behavior.