In science, buckling is a mathematical instability, leading to a failure mode. Theoretically, buckling is caused by a bifurcation in the solution to the equations of static equilibrium. At a certain stage under an increasing load, further load is able to be sustained in one of two states of equilibrium: an undeformed state or a laterally-deformed state.
In practice, buckling is characterized by a sudden failure of a structural member subjected to high compressive stress, where the actual compressive stress at the point of failure is less than the ultimate compressive stresses that the material is capable of withstanding. For example, during earthquakes, reinforced concrete members may experience lateral deformation of the longitudinal reinforcing bars. This mode of failure is also described as failure due to elastic instability. Mathematical analysis of buckling makes use of an axial load eccentricity that introduces a moment, which does not form part of the primary forces to which the member is subjected. When load is constantly being applied on a member, such as column, it will ultimately become large enough to cause the member to become unstable. Further load will cause significant and somewhat unpredictable deformations, possibly leading to complete loss of load-carrying capacity. The member is said to have buckled, to have deformed.
Read more about Buckling: Columns, Buckling Under Tensile Dead Loading, Constraint's Curvature and Multiple Buckling, Flutter Instability, Limit Point Vs Bifurcation Buckling, Bicycle Wheels, Surface Materials, Energy Method, Flexural-torsional Buckling, Lateral-torsional Buckling, Plastic Buckling, Dynamic Buckling, Buckling of Thin Cylindrical Shells Subject To Axial Loads, Buckling of Pipes and Pressure Vessels Subject To External Overpressure