Viscoelastic Material Characterization
Figure 4 describes the steps followed to determine the Prony series parameters as input for the finite-element model. After performing the creep-compliance test with the indirect tensile test (IDT), the master curve is constructed using a sigmoidal function; then the master curve (experimental data) is fitted to a power-law function. Using this power-law function and Laplace transform, the relaxation modulus in power-law representation is determined and approximated by a four-parameter Prony series as input for the finite-element calculation. Details of the work are shown below.