Distortional buckling is a type of instability that can occur in stiffeners like grooves or edge folds used to support slender plates and increase their resistance to local buckling. If the stiffener is not strong enough to resist the internal forces on it, the flange or web can experience local buckling, which significantly reduces the member's load capacity. The magnitude and direction of the applied loads, as well as the dimensions and material properties of the stiffener, affect the degree of distortion. Distortional buckling is sometimes also referred to as local distortional buckling or stiffener buckling.
To prevent distortional buckling, it is important to ensure that the stiffeners are adequately designed and sized to resist the internal forces. This can be achieved through appropriate choice of material, sizing, and shape of the stiffeners.