 ADIABATIC

Include this parameter to perform an adiabatic stress analysis. This
parameter is relevant only for isotropic metal plasticity materials with a
Mises yield surface and when the
INELASTIC HEAT FRACTION option has been specified.
 ALLSDTOL

Include this parameter to indicate that an adaptive automatic damping
algorithm will be activated in this step. Set this parameter equal to the
maximum allowable ratio of the stabilization energy to the total strain energy.
The initial damping factor is specified via the STABILIZE parameter or the FACTOR parameter. This damping factor will then be adjusted through
the step based on the convergence history and the value of ALLSDTOL. If this parameter is set equal to zero, the adaptive automatic
damping algorithm is not activated; a constant damping factor will be used
throughout the step. If this parameter is included without a specified value,
the default value is 0.05. If this parameter is omitted but the STABILIZE parameter is included with the default value of dissipated
energy fraction, the adaptive automatic damping algorithm will be activated
automatically with ALLSDTOL=0.05.
This parameter must be used in conjunction with the STABILIZE parameter (see
Solving nonlinear problems).
 CONTINUE

Set CONTINUE=NO (default) to specify that this step will not carry over the
damping factors from the results of the preceding general step. In this case
the initial damping factors will be recalculated based on the declared damping
intensity and on the solution of the first increment of the step or can be
specified directly.
Set CONTINUE=YES to specify that this step will carry over the damping factors
from the end of the immediately preceding general step.
This parameter must be used in conjunction with the ALLSDTOL and the STABILIZE parameters.
 DIRECT

This parameter selects direct user control of the incrementation through the
step. If this parameter is used, constant increments of the size defined by the
first item on the data line are used. If this parameter is omitted,
Abaqus/Standard
will choose the increments (after trying the user's initial time increment for
the first attempt at the first increment).
The parameter can have the value NO STOP. If this value is included, the solution to an increment is
accepted after the maximum number of iterations allowed has been completed (as
defined by the
CONTROLS option), even if the equilibrium tolerances are not
satisfied. Very small increments and a minimum of two iterations are usually
necessary if this value is used. This approach is not
recommended; it should be used only in special cases when the analyst has a
thorough understanding of how to interpret results obtained in this
way.
 FACTOR

Set this parameter equal to the damping factor to be used in the automatic
damping algorithm (see
Solving nonlinear problems)
if the problem is expected to be unstable due to local instabilities and the
damping factor calculated 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 when 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 maximum number of increments 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 longterm elastic
solution with timedomain viscoelasticity or the longterm elasticplastic
solution for twolayer viscoplasticity. If the LONG TERM parameter is omitted, the instantaneous elastic solution is
obtained for timedomain viscoelasticity and the combined response of the
elasticplastic and elasticviscous networks is obtained for twolayer
viscoplasticity. The parameter is relevant only for timedomain viscoelastic
and twolayer viscoplastic materials.
 RIKS

Include this parameter to use the modified Riks method for proportional
loading cases (Unstable collapse and postbuckling analysis).
 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).
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 $2\times {10}^{4}$
and the adaptive automatic damping algorithm will be activated by default with ALLSDTOL =0.05 in this step; set ALLSDTOL=0 to deactivate the adaptive automatic damping algorithm. If
the FACTOR parameter 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.