Buckling

Buckled skin panels on a B-52 aircraft. Thin skin panels buckle at very low loads. In the case shown here, the weight of the forward fuselage structure ahead of the nose undercarriage is sufficient to cause the panels to buckle. Buckled panels are still effective in carrying shear by diagonal tension.[1]

In structural engineering, buckling is the sudden change in shape (deformation) of a structural component under load, such as the bowing of a column under compression or the wrinkling of a plate under shear. If a structure is subjected to a gradually increasing load, when the load reaches a critical level, a member may suddenly change shape and the structure and component is said to have buckled.[2] Euler's critical load and Johnson's parabolic formula are used to determine the buckling stress of a column.

Buckling may occur even though the stresses that develop in the structure are well below those needed to cause failure in the material of which the structure is composed. Further loading may cause significant and somewhat unpredictable deformations, possibly leading to complete loss of the member's load-carrying capacity. However, if the deformations that occur after buckling do not cause the complete collapse of that member, the member will continue to support the load that caused it to buckle. If the buckled member is part of a larger assemblage of components such as a building, any load applied to the buckled part of the structure beyond that which caused the member to buckle will be redistributed within the structure. Some aircraft are designed for thin skin panels to continue carrying load even in the buckled state.

  1. ^ Cite error: The named reference bruhn73 was invoked but never defined (see the help page).
  2. ^ Elishakoff, I. Li Y-W. and Starnes, J.H. Jr., Non Classical Problems in the Theory of Elastic Stability, Cambridge University Press, 2001, XVI +pp.336; ISBN 0-521-78210-4