Combining Output from Substructures

The abaqus substructurecombine utility combines the model and results data produced by two of a model's substructures into a single output database (.odb) file.

Note: Using the abaqus odbcombine utility is the preferred method for combining the substructure output database (.odb) files.

Abaqus combines output data by adding the contents of the second file you specify (the copy output database) directly into the first file you specify (the base output database). Because this process changes the base output database, consider backing up your data before using this utility.

This page discusses:

Combining Data for Models with More than Two Substructures
Customizing the Combined Output Database
Command summary
Command line options
Examples

Combining Data for Models with More than Two Substructures

Because the abaqus substructurecombine utility combines data from only two output databases at a time, you must run the utility multiple times to create a single output database from an analysis with more than two substructures. Combine data from two of the substructures first, then repeat the operation to combine the resulting output database file with data from each remaining substructure.

Customizing the Combined Output Database

You can customize the substructure combine operation by adding only a subset of the data from the copy output database into the base output database. Abaqus enables you to add output data to the base output database from a single step or frame in the copy output database. You can also include only output data from the copy output database that relates to a particular variable; for example, you can copy output data related to Mises stress.

Command summary

abaqus substructurecombine baseodbodb-file-name copyodbodb-file-name all stepstep-name frameframe-number variablevariable-key

Command line options

baseodb

This option specifies the name of the base output database, to which Abaqus adds the contents of the copy output database.

If you omit this option from the command line, Abaqus will prompt you for its value.

copyodb

This option specifies the name of the copy output database, which Abaqus adds to the contents of the base output database. You can specify only one file at a time for this option.

If you omit this option from the command line, Abaqus will prompt you for its value.

all

This option indicates that data for all variables within all steps and frames of output should be copied to the combined output database. When you specify this option, Abaqus ignores the step, frame, and variable options.

step

This option indicates the name of the step from which Abaqus will copy results data. You can specify only one step; if you omit this option, Abaqus copies data from the last step in the output database.

Abaqus ignores this option if you specify the all option.

frame

This option indicates the number of the frame from which Abaqus will copy results data. You can specify only one frame; if you omit this option, Abaqus uses the last frame in the step specified by the step option.

Abaqus ignores this option if you specify the all option.

variable

This option indicates the variable key for the variable from which Abaqus will copy results data. If you omit this option, Abaqus copies data for all variables in the output database. Abaqus ignores this option if you specify the all option.

Only output variable keys that are valid for output database file output are available for use with abaqus substructurecombine. In general, if a key corresponds to a collective output variable, rather than an individual component, it can be used with this execution procedure. The collective output variable keys are distinguished from their individual components by the fact that they have the word "yes" after one of the .odb categories in the tables in Using Abaqus/Standard Output Variable Identifiers.

Examples

The following examples illustrate different methods of combining substructures using the abaqus substructurecombine execution procedure.

Combining Two Substructures

If your model contains two substructures that produce output database files named subst1.odb and subst2.odb, issue the following command to overwrite subst1.odb with the combined contents of the two files:

abaqus substructureCombine baseodb=subst1.odb copyodb=subst2.odb

Combining More than Two Substructures

If your model contains more than two substructures, you must first combine the output database files from two of the substructures, then combine the combined output database with each of the other substructures' output databases in turn. In this example the substructure analysis produces four output database files named subst1.odb, subst2.odb, subst3.odb and subst4.odb, so you must issue the abaqus substructure command a total of three times to combine all four files into a single output database, as shown in the following example:

abaqus substructureCombine baseodb=subst1.odb copyodb=subst2.odb
abaqus substructureCombine baseodb=subst1.odb copyodb=subst3.odb
abaqus substructureCombine baseodb=subst1.odb copyodb=subst4.odb

Combining Specific Elements of the Substructures

If you want to include only the output data from the step Step-1 in the combined output database, issue the following command:

abaqus substructureCombine baseodb=subst1.odb copyodb=subst2.odb
   step="Step-1"

If you want to include only the output data from the Mises variable in the combined output database, issue the following command:

abaqus substructureCombine baseodb=subst1.odb copyodb=subst2.odb
  
variable="Mises"