Shearing (physics)

In continuum mechanics, shearing refers to the occurrence of a shear strain, which is a deformation of a material substance in which parallel internal surfaces slide past one another.

A plastic shear strain is a continuous (non-fracturing) deformation that is irreversible, such that the material does not recover its original shape.

For those having two axes of symmetry, the shear center lies on the centroid of the cross-section.

In some materials such as metals, plastics, or granular materials like sand or soils, the shearing motion rapidly localizes into a narrow band, known as a shear band.

A special case of shear localization occurs in brittle materials when they fracture along a narrow band.

A wood-framed clapboard house, the walls WAY out of plumb.
The rectangularly-framed section has deformed into a parallelogram (shear strain), but the triangular roof trusses have resisted the shear stress and remain undeformed