What is shear failure?
Shear failure is the sliding or collapse of a material, soil layer or structural element caused by shear forces. In shear failure, two parts of the material slide past each other — similar to pushing a deck of cards sideways.
How does shear failure work?
Shear forces act parallel to the surface of a material, unlike compressive forces (which act perpendicular). When the shear stress exceeds the shear strength of the material, failure occurs.
This can happen in:
- Structures — a beam that fails at the support because the shear force is too high
- Soil — an embankment or slope that slides when the soil is overloaded or too wet
- Connections — a bolt connection that fails because the bolt is sheared through
Applications
- Structural design — engineers always check beams and supports for shear. Shear links (stirrups) in reinforced concrete beams prevent shear failure
- Geotechnical engineering — when designing embankments, slopes and excavations, the shear resistance of the soil is calculated
- Timber connections — mortise-and-tenon and notch joints are checked for shear along the grain
- Foundations — pile load tests measure, among other things, the shear resistance along the pile shaft
Related terms
- Shear force
- Structural failure
- Structural engineering
- Geotechnics
- Lateral force
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