ABAQUS Volume II: I–Z - Manual (Page 605)

*VISCO
21.3 *VISCO: Transient, static, stress/displacement analysis with time-dependent
material response (creep, swelling, and viscoelasticity).
This option is used to obtain a transient static response in an analysis with time-dependent material behavior
(creep, swelling, and viscoelasticity).
Product: ABAQUS/Standard
Type: History data
Level: Step
References:
•
“Quasi-static analysis,” Section 6.2.5 of the ABAQUS Analysis User’s Manual
•
“Rate-dependent plasticity: creep and swelling,” Section 18.2.4 of the ABAQUS Analysis User’s Manual
Optional parameters:
CETOL
Set this parameter equal to the maximum difference in the creep strain increment calculated from the
creep strain rates based on conditions at the beginning and on conditions at the end of the increment,
thus controlling the accuracy of the creep integration. In general, the tolerance can be calculated
by choosing an acceptable stress error tolerance and dividing by a typical elastic modulus. If the
model consists of a linear viscoelastic material characterized by the *VISCOELASTIC option, a
looser tolerance of the order of the elastic strains can be used. If CETOL is omitted, fixed time
increments are used.
CREEP
Set CREEP=EXPLICIT to use explicit integration for creep behavior throughout the step, which
may sometimes be computationally less expensive. The time increment will be limited by the
accuracy tolerance (CETOL) and by the stability limit of the forward difference operator. See
“Rate-dependent plasticity: creep and swelling,” Section 18.2.4 of the ABAQUS Analysis User’s
Manual, for details on the integration scheme.
FACTOR
Set this parameter equal to the damping factor to be used in the automatic damping algorithm
(see “Solving nonlinear problems,” Section 7.1.1 of the ABAQUS Analysis User’s Manual) if
the problem is expected to be unstable due to local instabilities and the damping factor calculated
by ABAQUS/Standard is not suitable. This parameter must be used in conjunction with the
STABILIZE parameter and overrides the automatic calculation of the damping factor based on a
value of the dissipated energy fraction.
21.3–1
ABAQUS Version 6.1 Module: ID:
Printed on: