when any 2 portions of the body remain the same
homogenous strain
when portions of the body change in shape
heterogenous strain
series of movements that affect a body from its initial to deformed state
progressive deformation
total strain acquired by the body up to time of measurement
strain rate
intermediate strain steps towards final configuration
incremental strain
measure of strain that compares initial and final
finite strain
the sequence of strain states through which the body passed
strain path
changes in the lengths of lines
linear strain
changes in the angles of lines
shear strain
amount a vertical line has been rotated
angular shear
changes in volume
volumetric strain
graphical representation of strain
strain ellipse
represents the cumulative and total deformation
finite strain ellipse
represents the strain for an instant in time
infinitesimal ellipse
represents the maximum stretch and elongation
stretching axis
represents the minimum stretch and elongation
shortening axis
describes how the shape of an spherical reference object would change as a result of deformation
strain ellipsoid
visualization of the range of possible strain ellipsoid shapes
flinn diagram
same orientation of strain axes
non-rotational
different orientation of strain axes
rotational
contraction and elongation are parallel to the strain axes; perfect coaxial deformation
pure shear
strain increments are all non-rotational
coaxial deformation
the directions of the principal strain rotate through different material lines
non-coaxial deformation
during deformation, the strain axes rotate; perfect non-coaxial deformation
simple shear
