Small deflection and small strain
analyses assume that displacements are small enough that the resulting
stiffness changes are insignificant
For small-strain regions of response,
true strain and engineering strain are essentially identical
In contrast, large strain
analyses account for the stiffness changes that result from changes in an element's shape and
orientation.
In large strain solutions,
all stress-strain input and results will be in terms of true stress and true (or
logarithmic) strain
