where Eq. (4) models the creep curve, while Eq. (5) characterizes
the creep-recovery process.
The time history data of creep strain in the creep regime was fitted with Eq. (4) using the least-square methods. Subsequently, the
estimated material parameters were then input to Eq. (5) to predict
the creep-recovery behavior. The model prediction was compared
to the experimental data in the creep-recovery regime to test the
predictive power of the Power-Law equation.