5.4. Using Special Solution Controls for Certain Types of Structural Analyses

When you are performing certain types of structural analyses, you can take advantage of these special solution tools:

5.4.1. Using Abridged Solution Menus

If you are using the GUI to perform a structural static, transient, modal, or buckling analysis, you can use either abridged or unabridged Solution menus:

  • Unabridged Solution menus list all solution options, regardless of whether it is recommended, or even possible, for you to use them in the current analysis. (If it is not possible for you to use an option in the current analysis, the option is listed but is grayed out.)

  • Abridged Solution menus are simpler. They list only those options that apply to the type of analysis that you are performing. For example, if you are performing a static analysis, the Modal Cyclic Sym option does not appear on the abridged Solution menu. Only those options that are valid and/or recommended for the current analysis type appear.

If you are performing a structural analysis, the abridged Solution menu appears by default when you enter the solution processor (Main Menu> Solution).

If your analysis is either static or full transient, you can use the options on the menu to complete the solution phase of your analysis. However, if you select a different analysis type, the default abridged Solution menu that you see above is replaced by a different Solution menu. The new menu is appropriate for the analysis type you select.

All variants of the abridged Solution menu contain an Unabridged Menu option. This option is always available for you to select in case you prefer using the unabridged menu.

If you perform one analysis and then start a new analysis within the same session, the program (by default) presents you with the same type of Solution menu that you used for the first analysis. For example, if you choose to use the unabridged Solution menu to perform a static analysis and then select a new buckling analysis, the unabridged Solution menu that is appropriate for buckling analyses appears. You can toggle between the unabridged and abridged Solution menus at any time during the solution phase of the analysis by selecting the appropriate menu option (Main Menu> Solution> Unabridged Menu or Main Menu> Solution> Abridged Menu).

5.4.2. Using the Solution Controls Dialog Box

If you are performing a structural static or full transient analysis, you can use a streamlined solution interface (called the Solution Controls dialog box) for setting many of your analysis options. The Solution Controls dialog box consists of five tabbed "pages," each of which contains a set of related solution controls. The dialog box is useful for specifying the settings for each load step of a multiple load step analysis.

As long as you are performing a structural static or full transient analysis, your Solution menu contains the Sol'n Control option. When you click the Sol'n Control menu item, the Solution Controls dialog box appears. This dialog box provides you with a single interface for setting analysis and load step options. See Figure 5.1: Solution Controls Dialog Box for an illustration.

Figure 5.1: Solution Controls Dialog Box

Solution Controls Dialog Box


The Basic tab, which is shown above, is active when you access the dialog box. The complete list of tabs, in order from left to right, is as follows:

  • Basic

  • Transient

  • Sol'n Options

  • Nonlinear

  • Advanced NL

Each set of controls is logically grouped on a tab; the most basic controls appear on the first tab, with each subsequent tab providing more advanced controls. The Transient tab contains transient analysis controls; it is available only if you choose a transient analysis and remains grayed out when you choose a static analysis.

Each of the controls on the Solution Controls dialog box corresponds to a command. The table below illustrates the relationships between the tabs and the command functionality that you can access from each.

Table 5.3: Relationships Between Tabs of the Solution Controls Dialog Box and Commands

Solution Controls Dialog Box TabWhat Does This Tab Enable You to Do?What Commands Are Related to This Tab?
Basic
Specify the type of analysis that you want to perform.
Control various time settings.
Specify the solution data that you want to write to the database.
Specify the prestress effects.
ANTYPE, NLGEOM, TIME, AUTOTS, NSUBST, DELTIM, OUTRES, PSTRES
Transient
Specify transient options, such as transient effects and ramped vs. stepped loading.
Specify damping options.
Choose time integration method.
Define integration parameters.
Set midstep residual criterion.
TIMINT, KBC, ALPHAD, BETAD, TRNOPT, TINTP, MIDTOL
Sol'n Options
Specify the type of equation solver that you want to use.
Specify parameters for performing a multiframe restart.
EQSLV, RESCONTROL,
Nonlinear
Control nonlinear options, such as line search and solution predictor.
Specify the maximum number of iterations that are allowed per substep.
Indicate whether you want to include creep calculation in the analysis.
Control bisections.
Set convergence criteria.
Specify the creep strain rate effect.
LNSRCH, PRED, NEQIT, RATE, CUTCONTROL, CNVTOL, RATE
Advanced NL
Specify analysis termination criteria.
Control activation and termination of the arc-length method.
Active elements that support nonlinear stabilization.
NCNV, ARCLEN, ARCTRM, SSTATE

When you are satisfied with the settings on the Basic tab, you do not need to progress through the remaining tabs unless you want to change some of the advanced controls. As soon as you click OK on any tab of the dialog box, the settings are applied to the database and the dialog box closes.

Whether you make changes to only one or to multiple tabbed pages, your changes are applied to the database only when you click OK to close the dialog box.

5.4.3. Accessing More Information

Discussions of the Solution Controls dialog box are included throughout this documentation as applicable.

For additional information, refer to the following: