This option is used to generalize a material's elastic response to include viscoelasticity. The viscoelasticity can be defined as a function of frequency for steady-state small-vibration analyses or as a function of reduced time for time-dependent analyses.
Products: ABAQUS/Standard ABAQUS/Explicit
Type: Model data
Level: Model
This parameter applies only to ABAQUS/Standard analyses.
Use this parameter to choose the frequency domain definition. In this case the material's long-term elasticity must be defined using the *ELASTIC or the *HYPERELASTIC option.
Set FREQUENCY=CREEP TEST DATA to define the frequency domain response using a Prony series representation of the relaxation moduli, if the Prony series parameters are to be computed from shear and volumetric creep test data.
Set FREQUENCY=FORMULA to define the dissipative material parameters by the power law formulæ.
Set FREQUENCY=PRONY to define the frequency domain response using a Prony series representation of the relaxation moduli by specifying the Prony series parameters.
Set FREQUENCY=RELAXATION TEST DATA to define the frequency domain response using a Prony series representation of the relaxation moduli, if the Prony series parameters are to be computed from shear and volumetric relaxation test data.
Set FREQUENCY=TABULAR to provide tabular definition of the frequency domain response.
Use this parameter to choose the time domain definition. In this case the material's elasticity must be defined using the *ELASTIC, the *HYPERELASTIC, or the *HYPERFOAM option.
Set TIME=CREEP TEST DATA if the Prony series parameters are to be computed by ABAQUS from data taken from shear and volumetric creep tests.
Set TIME=FREQUENCY DATA if the Prony series parameters are to be computed by ABAQUS from frequency-dependent cyclic test data.
Set TIME=PRONY to define a linear, isotropic, viscoelastic material by giving the parameters of the Prony series representation of the relaxation moduli.
Set TIME=RELAXATION TEST DATA if the Prony series parameters are to be computed by ABAQUS from data taken from shear and volumetric relaxation tests.
Set this parameter equal to the allowable average root-mean-square error of the data points in the least-squares fit. The default is 0.01 (1%).
Set this parameter equal to the maximum number of terms 
in the Prony series. ABAQUS will perform the least-squares fit from 
to 
NMAX until convergence is achieved for the lowest with respect to ERRTOL. The default and maximum value is 13.
First (and only) line:
Real part of 
. 
Imaginary part of .
Value of 
.
Real part of 
. 
If the material is incompressible, this value is ignored.
Imaginary part of . If the material is incompressible, this value is ignored.
Value of 
. If the material is incompressible, this value is ignored.
First line:
Real part of 
. 
Imaginary part of . 
Real part of 
. 
If the material is incompressible, this value is ignored.
Imaginary part of . 
If the material is incompressible, this value is ignored.
Frequency 
in cycles per time.
Repeat this data line as often as necessary to define the dissipative part of the material behavior.
First line:
, the modulus ratio in the first term in the Prony series expansion of the shear relaxation modulus.
, the modulus ratio in the first term in the Prony series expansion of the bulk relaxation modulus.
, the relaxation time for the first term in the Prony series expansion.
Repeat this data line as often as necessary to define the second, third, etc. terms in the Prony series. There is no restriction on the number of terms in the Prony series.
No data lines are used with this option when either TIME=CREEP TEST DATA or TIME=RELAXATION TEST DATA is specified. The test data are given by the *SHEAR TEST DATA and the *VOLUMETRIC TEST DATA options or by the *COMBINED TEST DATA option.