Strain

Topics

• Torsion
• Shear Strain
• Strain Energy

$\epsilon =\frac{\Delta L}{L}$

• $\Delta L$ is the change in length of an object in response to a force
• $L$ is the length of the object without forces

$\epsilon =\frac{1}{2}(\nabla \vec{u}+\nabla {\vec{u}}^T)$

• $\vec{u}$ is the displacement vector field
• Is the symmetric component of $\nabla \vec{u}$
• From this video
• Taking the gradient gives a tensor
• Used for strains < 2%