This option is used when metal creep behavior is to be included in a
material definition. Metal creep behavior defined is active only during
DIRECT CYCLIC;
SOILS, CONSOLIDATION;
COUPLED TEMPERATURE-DISPLACEMENT;
STEADY STATE TRANSPORT; and
VISCO procedures. This option can also be used to define creep
behavior in the thickness direction in a gasket; in this case the option is
active only during the
VISCO procedure.
Set this parameter equal to the number of field variable dependencies
included in the definition of the creep constants in addition to temperature.
If this parameter is omitted, it is assumed that the creep constants have no
dependencies or depend only on temperature.
See Material Data Definition for more information.
LAW
Set LAW=STRAIN (default) to choose a strain hardening law. This parameter
setting is superseded by LAW=POWER LAW.
Set LAW=TIME to choose a time hardening law. This parameter setting is
superseded by LAW=TIME POWER LAW.
Set LAW=HYPERB to choose a hyperbolic-sine law.
Set LAW=USER to input the creep law using user subroutine
CREEP.
Set LAW=ANAND to choose an Anand law.
Set LAW=DARVEAUX to choose a Darveaux law.
Set LAW=DOUBLE POWER to choose a double power law.
Set LAW=POWER LAW to choose a power law. It is recommended that you use this
parameter setting rather than LAW=STRAIN.
Set LAW=TIME POWER LAW to choose a time power law. It is recommended that you use
this parameter setting rather than LAW=TIME.
TIME
This parameter is relevant only when LAW=TIME or LAW=TIME POWER LAW is used.
Set TIME=CREEP to use creep time.
Set TIME=TOTAL (default) to use total time.
Data lines for LAW=TIME or LAW=STRAIN
First
line
A. (Units of FLT.)
n.
m.
Temperature.
First field variable.
Second field variable.
Etc., up to four field variables.
Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
Fifth field variable.
Etc., up to eight field variables per line.
Repeat this set of data
lines as often as necessary to define the dependence of the creep constants on
temperature and other predefined field
variables.
Data lines for LAW=HYPERB
First
line
A. (Units of T−1.)
B. (Units of
F−1L2.)
n.
.
(Units of JM−1.) (This value can be left blank if
temperature dependence is not needed.)
R. (Units of
JM−1−1.)
First field variable.
Second field variable.
Third field variable.
Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than three)
Fourth field variable.
Etc., up to eight field variables per line.
Repeat this set of data
lines as often as necessary to define the dependence of the creep constants on
predefined field
variables.
Data lines for LAW=ANAND
First
line
S1. (Units of
FL−2.)
.
(Units of .)
A. (Units of T−1.)
.
m.
A0. (Units of
FL−2.)
.
(Units of FL−2.)
n.
Second line
a.
S2. (Units of
FL−2.)
S3. (Units of
FL−2.)
A1. (Units of
FL−2.)
A2. (Units of
FL−2.)
A3. (Units of
FL−2T.)
A4. (Units of
FL−2T2.)
Data lines for LAW=DARVEAUX
First
line
Css. (Units of
T−1.)
.
(Units of .)
.
(Units of F−1L2.)
n.
.
B.
Data lines for LAW=DOUBLE POWER
First
line
A1. (Units of
T−1.)
B1. (Units of
.)
C1.
A2. (Units of
T−1.)
B2. (Units of
.)
C2.
.
(Units of FL−2.)
Data lines
for LAW=POWER LAW
First
line
.
(Units of FL−2.)
n.
m.
Blank space.
.
The default is 1.0. (Units of T−1.)
Temperature.
First field variable.
Second field variable.
Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than two)
Third field variable.
Etc., up to eight field variables per line.
Repeat this set of data
lines as often as necessary to define the dependence of the creep constants on
temperature and other predefined field
variables.
Data
lines for LAW=TIME POWER LAW
First
line
.
(Units of FL−2.)
n.
m.
.
The default is 1.0. (Units of T−1.)
Temperature.
First field variable.
Second field variable.
Third field variable.
Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than three)
Fourth field variable.
Etc., up to eight field variables per line.
Repeat this set of data
lines as often as necessary to define the dependence of the creep constants on
temperature and other predefined field
variables.