Mechanical APDL Structural Analysis Guide

Special considerations for setting these options in a full transient analysis include:

• TIMINT is a dynamic load step option that specifies whether time integration effects are on or off. Time
  integration effects must be turned on for inertia and damping effects to be included in the analysis (oth-
  erwise a static solution is performed), so the default is to include time integration effects. This option is
  useful when beginning a transient analysis from an initial static solution; that is, the first load steps are
  solved with the time integration effects off.


• ALPHAD (alpha, or mass, damping) and BETAD (beta, or stiffness, damping) are dynamic load step options
  for specifying damping options. Damping in some form is present in most structures and should be included
  in your analysis. See Damping Option (p. 116) for other damping options.


• TRNOPT (TINTOPT) specifies the time integration method to be used. The default is Newmark method.


• TINTP is a dynamic load step option that specifies transient integration parameters. Transient integration
  parameters control the nature of the Newmark and HHT time integration techniques.

5.3.3.4. Using the Remaining Solution Controls Tabs

The options on the remaining tabs in the Solution Controls dialog box for a full transient analysis are
the same as the ones you can set for a static structural analysis. See the following sections of Structural
Static Analysis (p. 9) for a list of these options:

• Using the Sol'n Options Tab (p. 12)


• Using the Nonlinear Tab (p. 12)


• Using the Advanced NL Tab (p. 13). Exception: You cannot use arc-length options in a full transient ana-
  lysis.

5.3.3.4.1. Set Additional Solution Options.

The additional solution options that you can set for a full transient analysis are mostly the same as the
ones you can set for a static structural analysis. For a general description of what additional solution
options are, along with descriptions of those options that are the same, see the following sections of
Structural Static Analysis (p. 9):

• Set Additional Solution Options (p. 13)


• Stress Stiffening Effects (p. 13)


• Newton-Raphson Option (p. 14)


• Creep Criteria (p. 15)


• Printed Output (p. 15)


• Extrapolation of Results (p. 15)

Additional solution options for a full transient analysis that differ from those for a static analysis, or
have different descriptions are presented in the following sections.

You may also use the NLHIST command to monitor results of interest in real time during solution. Before
starting the solution, you can request nodal data such as displacements or reaction forces at specific
nodes. You can also request element nodal data such as stresses and strains at specific elements to be

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Performing a Full Transient Dynamic Analysis