Buckling

Summary

Buckling is the sudden sideways deflection of a slender structure, such as a column, plate or shell, under compressive load. It happens at a critical load where the straight or flat equilibrium becomes unstable and a bent shape becomes possible. So it is a case of elastic instability. The critical load can be far below the load that would crush the material, so buckling often decides the strength of slender parts. For columns the basic result is Euler's critical load.