*
STATIC
by ABAQUS 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.
This parameter cannot be used if the RIKS parameter is included.
FULLY PLASTIC
This parameter is relevant only for cases where “fully plastic” analysis is required with deformation
theory plasticity. For that purpose set this parameter equal to the name of the element set being
monitored for fully plastic behavior.
The step will end w hen the solutions at all constitutive calculation points in the element set are
fully plastic (defined by the equivalent strain being 10 times the offset yield strain). The step will
end before this occurs if either the maxim um number of increm ents given on the
*
STEP option or
the time period given on the data line of
*
STATIC is exceeded.
LONG TERM
Include this parameter to obtain the fully relaxed long-term elastic solution with time-domain
viscoelasticity or the long-term elastic-plastic solution for two-layer viscoplasticity. If the LONG
TERM parameter is omitted, the instantaneous elastic solution is obtained for time-domain
viscoelasticity and the combined response of the elas tic-plastic and elastic-viscous networks is
obtained for two-layer viscoplasticity. The param eter is relevant only for time-domain viscoelastic
and two-layer viscoplastic materials.
RIKS
Include this parameter to use the modified Riks method for proportional loading cases (“U nstable
collapse and postbuckling analysis,” Section 6.2.4 of the ABAQUS Analysis User’s Manual).
STABILIZE
Include this parameter to use automatic stabilization if the problem is expected to be unstable due
to local instabilities. Set this parameter equal to the dissipated energy fraction of the automatic
damping algorithm (see “Solving nonlinear problems,” Section 7.1.1 of the ABAQUS Analysis
User’s Manual). If this parameter is omitted , the stabilization algorithm is not activated. If this
parameter is included without a specified value, the default value of the dissipated energy fraction
is
. If the FACTOR param eter is used, any value of the dissipated energy fraction will be
overridden by the damping factor.
This parameter cannot be used if the RIKS parameter is included.
Data line for a general static analysis:
First (and only) line:
1. Initial time increment. This value will be modified as re quired if the automatic time stepping
scheme is used or will be used as the constant time increment if the DIRECT parameter is used.
If this entry is zero or is not specified, a default value that is equal to the total time period of
the step is assumed.
2. Time period of the step. If this entry is zero or is not specified, a default value of
is assumed.
18.31–2
ABAQUS Version 6.1 Module:
ID:
Printed on:
