Abaqus can create the following output files during an analysis:
a data file containing printed output of the model and history definition generated by
the analysis input file processor and, in Abaqus/Standard, printed output of results written during the analysis run;
an ODB output database file containing results for
postprocessing with the Visualization module of Abaqus/CAE (Abaqus/Viewer) and, in Abaqus/Standard, diagnostic information;
a SIM database file containing results for
high-performance postprocessing with the Physics Results Explorerapp
on the 3DEXPERIENCE platform;
a selected results file in Abaqus/Explicit;
a results file containing results for postprocessing with external software in Abaqus/Standard and Abaqus/Explicit (in Abaqus/Explicit this file is generated by converting the selected results file);
a message file containing diagnostic messages about the solution in Abaqus/Standard and Abaqus/Explicit; and
a status file containing information about the status of the analysis and, in Abaqus/Explicit, diagnostic messages and information about the stable time increment.
Abaqus can create files for restarting an analysis—see Restarting an Analysis. In Abaqus/Standard these files can also be used to extract results output not requested during an analysis.
The data file (job-name.dat) is a text file
that contains information about the model definition (generated by the analysis input file processor) and, in Abaqus/Standard, tabular output of results. The analysis input file processor information includes the model definition, the history definition, and messages
identifying any error and warning conditions that were detected while processing the input
data.
Controlling the Amount of analysis input file processor Information Written to the Data File
You can control the amount of information written to the data file by the analysis input file processor in Abaqus/Standard and Abaqus/Explicit.
Input File Usage
Use the following option in the model definition section of the input file:
By default, the input file will not be echoed to the data file. You can choose to
activate this printout. If the input file is defined in terms of an assembly of part
instances, the echo to the data file will be that of the flattened input file (that is,
one that does not use parts and assemblies).
Job module: job editor: General: Preprocessor Printout: Print an echo of the input data
Input Parameter Information
For parametrized input files, information about input parameters and their values can
be printed in the data file. By default, the modified version of the original input file
showing this information will not be printed in the data file. You can choose to
activate this printout.
Parametrized input files are not supported in Abaqus/CAE.
Parameter-Free Input File Information
For parametrized input files, a parameter-free version (after parameter evaluation and
substitution) of the original input file can be printed in the data file. By default,
this modified version of the input file will not be printed in the data file. You can
choose to activate this printout.
Parametrized input files are not supported in Abaqus/CAE.
Model and History Definition Summaries
By default, the options defining the model and history data will not be summarized in
the data file. You can choose to activate this printout.
For an Abaqus/Explicit analysis the model summary data, when requested, includes the mass, center of mass,
and the rotary inertia information for the element sets in the model and for the whole
model. However, for two-dimensional models the reported rotary inertia includes the component corresponding to the only active rotation degree of freedom;
the remaining components are not included.
Job module: job editor: General: Preprocessor Printout: Print model definition data and Print history data
Contact Constraint Information
In Abaqus/Standard you can choose to activate printout of detailed information about the contact
constraints generated by the contact pair definition data.
In Abaqus/Standard the values of output variables can be printed to the data file in tabular format
throughout the analysis. You can control the following types of printed output during the
analysis run: element output, node output, contact surface output, energy output, fastener
interaction output, modal output, section output, and radiation output—see Output to the Data and Results Files and Cavity Radiation in Abaqus/Standard. You specify
the variables to be printed in each output table and, for element variables, the locations
at which they are to be printed (at the integration points, at the element centroid, at
the nodes, or averaged at the nodes). Nodal variables at nodes with transformations can be
written in either the global or the local coordinate system (see Transformed Coordinate Systems). The list of
available variables is given in Abaqus/Standard Output Variable Identifiers. Output of
results to the data file is requested as part of a step definition.
Viewing Part and Assembly Information in the Data File
An Abaqus model can be defined in terms of an assembly of part instances (see Assembly Definition). In such a
model node and element numbers can be repeated within the definitions of different parts.
These local numbers are converted internally by Abaqus to unique global numbers, and the output written to the data file is given in terms of
those internal numbers. A map between user-defined numbers and internal numbers is printed
to the data file (after the step data) if any output that includes node and element
numbers is requested in the data file.
Set and surface names that appear in the data file are prefixed by the assembly and part
instance names, separated by underscores
(Assembly_Part1–1_setname, for example).
Local coordinate systems defined within a part or part instance are translated and
rotated according to the positioning data given in the part instance definition.
The Output Database
The output database is a neutral binary file. Unlike the restart or binary results files,
it can be copied directly from one computing platform to another without translation.
Format of the Output Database
The Abaqus output database is available in two formats, ODB and
SIM. By default, the results output is created in
ODB format. For an Abaqus/Standard or Abaqus/Explicit analysis you have the option to write results in both formats during the same job. Only
results in SIM format can be imported into the 3DEXPERIENCE platform for high-performance postprocessing. For more information, see Limitations When Writing and Postprocessing Results in SIM Format below.
The ODB output database
(job-name.odb) is used to store
model information and analysis results in terms of an assembly of part instances. The Visualization module of Abaqus/CAE (Abaqus/Viewer) uses this output database for postprocessing analysis results and viewing
diagnostic information.
The SIM database file
(job-name.sim) contains model and
results information. The Physics Results Explorerapp on the 3DEXPERIENCE platform uses this database for high-performance postprocessing of analysis results.
Input File Usage
Use the following command line options to write results in an Abaqus/Standard or Abaqus/Explicit analysis in SIM format:
abaqusjob=job-nameresultsformat=sim
Use the following command line options to write results in an Abaqus/Standard or Abaqus/Explicit analysis in ODB format and in
SIM format:
abaqusjob=job-nameresultsformat=both
Abaqus/CAE Usage
Use the following input to write results in an Abaqus analysis in SIM format:
Use the following input to write results in an Abaqus/Standard or Abaqus/Explicit analysis in ODB format and in
SIM format:
Job module: job editor: General: Results Format: Both
Handling of Floating Point Data
By default, floating point data are written in single precision to the
ODB output database file. You can choose to write
floating point nodal field output data to the ODB
output database file in double precision; see Abaqus/Standard and Abaqus/Explicit Execution for details.
For Abaqus/Standard and Abaqus/Explicit analyses, floating point data are written to the SIM
database in single precision, with the exception of nodal coordinates, which are written
in double precision.
Opening an Output Database in Abaqus/CAE
You can open an output database file from an older release of Abaqus in Abaqus/CAE. Output database files from previous releases of Abaqus must be converted to the current release when they are opened. If you are using an
older release of Abaqus/CAE, you cannot open an output database file created from a newer release of Abaqus.
Choosing an Output Format
Your choice of output format depends on your level of experience with high-performance
visualization, the Physics Results Explorerapp,
and your postprocessing needs.
If you are still learning to use high-performance visualization and you want to
compare your results with Abaqus/Viewer, write results in both formats.
If the model is large and you need the improved performance of the Physics Results Explorerapp,
as well as the capabilities of Abaqus/Viewer, write results in both formats.
If you are confident that the high-performance visualization features in the Physics Results Explorerapp
provide all the capabilities you need, write results in
SIM format.
Requesting Output to the Output Database
You choose the variables to be written to the output database from the lists in Abaqus/Standard Output Variable Identifiers and Abaqus/Explicit Output Variable Identifiers. The
following types of output are available: element output, node output, contact surface
output, energy output, integrated output, time incrementation output, fastener interaction
output, modal output, and radiation output. In addition, a subset of the diagnostic
information that is written to the message file in Abaqus/Standard and Abaqus/Explicit (see The Message File in Abaqus/Standard and Abaqus/Explicit) and to the Abaqus/Explicit status file (see The Status File) is
included in the output database. See Output to the Output Database
for a detailed explanation of how to generate output database requests.
Three types of information are stored in the output database: “field” output, “history”
output, and diagnostic information. Field output is intended to be relatively infrequent
output for a large portion of the model.Abaqus/CAE uses field output to generate contour plots, displaced shape plots, symbol plots, and
X–Y plots in the Visualization module. History output is intended to be output for a small portion of the model
requested at a fairly high frequency.Abaqus/CAE uses history output to generate X–Y plots in the Visualization module.See Output to the Output Database
for detailed descriptions of field and history output. Diagnostic information is intended to provide convergence information for use in Abaqus/CAE; for more information, see Viewing diagnostic output.
Limitations When Writing and Postprocessing Results in
SIM Format
A subset of options in Abaqus/Standard and Abaqus/Explicit are not supported for analyses that produce results in
SIM format. If you include one or more of these options
or parameters in your analysis and write output in SIM
format or both formats, the analysis will either terminate with errors or produce limited
results.
The following options produce error messages in the data (.dat)
file:
The Abaqus/Explicit selected results file (job-name.sel)
stores user-selected results, which are converted into the results file
(job-name.fil) for postprocessing by
other commercial postprocessing packages.
Element output, node output, and energy output can be requested (see Output to the Data and Results Files for details); the variables available for output are
listed in Abaqus/Explicit Output Variable Identifiers. You can write a user-selected subset of
the results for a given node set or element set at more frequent intervals than the restart
intervals. You specify the output requests within a step definition, which allows you to be
selective about the amount of data written to the selected results file to avoid using
excessive disk storage. For example, when dealing with a very large model, you may choose to
write only the current displacements and the equivalent plastic strain for the entire model
20 times in the step and to write the acceleration history at one node 200 times in the
step.
The Results File
The Abaqus results file in Abaqus/Standard and Abaqus/Explicit (job-name.fil) can be read by external
postprocessors to produce X–Y plots or printed tabular output.
Most commercial finite element results-display packages provide translators that use the Abaqus results file as their input. The results file can also be used as a convenient medium for
importing analysis results into your own postprocessing program. Accessing the Results File Information provides details on how to read this file.
Results file output of temperature from a heat transfer, thermal-electrical, or
thermal-electrical-structural analysis can be used as input to a stress analysis of the same
mesh (see Sequentially Coupled Thermal-Stress Analysis).
Obtaining Results File Output in Abaqus/Standard
In Abaqus/Standard you choose the variables to be written to the results file from the lists in Abaqus/Standard Output Variable Identifiers in a manner similar to that for output printed to
the data file. You must specifically request that values be written to the results file or
none will be provided. Element output, node output, contact surface output, energy output,
modal output, and radiation output are available—see Output to the Data and Results Files and Cavity Radiation in Abaqus/Standard for details.
Obtaining Results at the Beginning of a Step
You can request that the solution state at the beginning of a step (the zero increment)
be written to the Abaqus/Standard results file. Zero-increment file output is available only for steps in which the
concept of time governs the incrementation scheme of the selected procedure and, hence,
the following procedures are excluded:
If you request zero-increment results file output, it will be generated for all valid
procedures in a given analysis.
You must request zero-increment results file output to generate a zero-increment
results file in a data check analysis (see Abaqus/Standard and Abaqus/Explicit Execution). It is
strongly recommended that you request zero-increment results file output if the results
file is used to drive a submodel; see Node-Based Submodeling for further
discussion.
The FILE FORMAT option can be
given as model data or as history data, but it can appear only once in the input
file.
Abaqus/CAE Usage
Results file output cannot be requested in Abaqus/CAE.
Obtaining Results File Output in Abaqus/Explicit
The Abaqus/Explicit results file is a sequential access file generated from the selected results file (see
Abaqus/Standard and Abaqus/Explicit Execution). The results
file contains the requested results in the format described in Results File.
Input File Usage
Use either of the following command line options to convert a selected results file
to a results file:
abaqusjob=job-nameconvert=select
abaqusjob=job-nameconvert=all
Abaqus/CAE Usage
The selected results file cannot be converted in Abaqus/CAE.
Part and Assembly Information
An Abaqus model can be defined in terms of an assembly of part instances (see Assembly Definition). However, the
results file does not contain part and assembly records.
In a model defined in terms of an assembly of part instances, node and element numbers
can be repeated within the definitions of different parts. These local numbers are
converted internally by Abaqus to unique global numbers, and the output written to the results file is given in terms
of the global (internal) numbers. A map between user-defined numbers and internal numbers
is printed to the data file if any results file output that includes node and element
numbers is requested.
Set and surface names that appear in the results file are prefixed by the assembly and
part instance names, separated by underscores
(Assembly_Part1–1_setname, for example).
Local coordinate systems defined within a part or part instance are translated and
rotated according to the positioning data given in the part instance definition.
Format of the Results File
The Abaqus results file in Abaqus/Standard or Abaqus/Explicit is organized as a sequential file, in binary or in
ASCII format. ASCII
format is necessary if the file is to be read on a computer system that is different from
the one on which the file was written. ASCII format
allows the results file to be transferred between different computer systems without
having to translate binary data. ASCII format is not
needed if the file will always be used on the same system or on systems that use the same
binary format. If the results file output will always reside on the same computer, the
default binary format is usually the most efficient way of storing the file. For large
problems a file in ASCII format will be significantly
larger than the same file in binary format.
Controlling the Format of the Results File in Abaqus/Standard
Abaqus/Standard can write the results file in either binary or ASCII
format. The default format is binary.
The results file output must be written in the same format for the entire analysis. The
format cannot be changed upon restarting the problem.
The format of the Abaqus/Standard results file can also be controlled in the Abaqus/Standard environment file (see Environment File Settings). The format
specified in an analysis supersedes the value defined in the environment file.
In addition, the ascfil facility in the Abaqus execution procedure (ASCII Translation of Results (.fil) Files) can be used
to convert a binary Abaqus/Standard results file (job-name.fil) to
ASCII format
(job-name.fin) after the analysis
completes.
The FILE FORMAT option can be
given as model data or as history data, but it can appear only once in the input
file.
Abaqus/CAE Usage
Results file output cannot be requested in Abaqus/CAE.
Controlling the Format of the Results File in Abaqus/Explicit
Abaqus/Explicit always writes the results file output in binary format during file conversion, but
the binary Abaqus/Explicit results file can be converted to ASCII format using
the ascfil facility (ASCII Translation of Results (.fil) Files).
ASCII Format
Results File defines the contents of the records that are
written to the results file; these descriptions also hold if the results file is written
in ASCII format. All the data items in these files are
either integers, floating point numbers, or character strings. When
ASCII format is requested, each data item is
translated into an equivalent character string before it is written to the file. These
strings are written in 80-character logical records in the order described in the record
definitions.
Each 80-character logical record is completely filled before the next one is started,
so that any data item can be split, with some of the characters that define the item in
one logical record and the remainder in the next. Each data item usually follows
immediately behind its predecessor. The exception is that for results file record key
2001 Abaqus will fill out the logical record with blank characters, so that the record can be
written immediately to the physical storage medium. Abaqus then inserts a logical record consisting of 80 blanks, which allows the end-of-file
to be handled correctly.
The beginning of each “record” is indicated by an asterisk (*). Each floating point
number begins with the character D, followed by the number in the format E22.15 or
D22.15, depending on whether the release of Abaqus that wrote the results file used single precision or double precision. Each character
string begins with the character A, followed by eight characters (if the character
string has fewer than eight characters, the right part of the string is blank; character
strings longer than eight characters are written eight characters at a time). Each
integer begins with the character I, followed by a two digit integer giving the number
of decimal digits in the integer, followed by the integer itself (written as decimal
digits).
For example, record key 1900 for an S4R
element with element number 5 and nodes 195, 198, 205, and 204 would be written
*I 18I 41900I 15AS4R I 3195I 3198I 3205I 3204
and record key 101 for node 135 and 6 degrees of freedom would be written
Precision of Floating Point Data in the Results File
The precision of floating point data written to the results file depends on the
precision of the executable that generates the data. Abaqus/Standard always uses double precision; thus, floating point data are always written to the Abaqus/Standard results file in double precision. Abaqus/Explicit can be run in single or double precision on most machines; see Defining an Analysis for details
on the precision level of the Abaqus/Explicit executable. If the double precision executable for Abaqus/Explicit is used, floating point data are written to the Abaqus/Explicit results file in double precision; likewise, if the single precision executable for
Abaqus/Explicit is used, floating point data are written to the Abaqus/Explicit results file in single precision.
Maximizing the Efficiency of the Results File
In Abaqus/Standard each element output request (a collection of identifying keys entered on a single line)
is preceded by an “element header” record (see Results File).
Hence, the size of the results file can be minimized by entering all element output
variables of the same “type” (element integration point variable, element section
variable, whole element variable, etc.) on a single line. (See Output to the Data and Results Files for an explanation of the output variable types.)
Consolidating output variable entries is encouraged, since it will reduce the size of the
results file.
Example
For example, the following output requests can be used to request output of element
variables in the results file in a stress/displacement analysis:
EL FILES, SINV, E, PE, CE, EE, ENER, TEMP, FV, COORDSF, SELOADS, ELEN, EVOLEL FILE, REBARS, SINV, E, PE, CE, EE, RBFOR, RBANGSF, SELOADS, ELEN
(The output requests for rebar quantities need not be the same as the underlying
element output requests.)
The Message File in Abaqus/Standard and Abaqus/Explicit
The message file (job-name.msg) is a text
file that contains diagnostic messages about the progress of the solution.
The Abaqus/Standard Message File
In Abaqus/Standard the message file contains diagnostic or informative messages about the progress of the
solution. If any of these messages describe errors or warnings, the number of such errors
or warnings is also given at the end of the data file. The message file is written
automatically during an Abaqus/Standard analysis.
The Abaqus/Standard message file contains information about the increment number, step time, fraction of a
step completed, equilibrium iterations, severe discontinuity (contact) iterations,
plasticity algorithms, adaptive mesh smoothing, the load proportionality factor in a Riks
analysis, etc. A portion of the diagnostic information in the
message file is also written to the output database for use in Abaqus/CAE (for more information, see Requesting Output to the Output Database).
You can control the amount of information written to the message file for each step. This
feature is sometimes helpful in difficult analyses since it allows detailed diagnostic
information to be written about certain events (such as contact) during a nonlinear
solution; this information can often be useful in developing a strategy for the solution
of highly nonlinear problems.
The PRINT option can appear only
once within a step definition.
Abaqus/CAE Usage
Step module: OutputDiagnostic Print
Controlling the Frequency of Output to the Message File
You can control the frequency at which information is printed to the message file by
specifying the desired output frequency in increments. The default output frequency is 1
(or 10 in a direct cyclic or a low-cycle fatigue analysis). The output will always be
printed at the last increment of each step unless you specify a frequency of zero to
suppress the output.
You can obtain a detailed printout of contact conditions during iteration. This
information about which points are contacting or separating in interface and gap
problems is useful in tracking the development of the solution in difficult contact
problems. The details are written for every severe discontinuity iteration. By default,
the detailed contact output is suppressed.
Step module: OutputDiagnostic Print: toggle on Contact
Requesting Detailed Model Change Printout
You can obtain a detailed printout of model change operations (removal and
reactivation) at the start of a step. This information includes the new original
coordinates and normals of elements being reactivated strain free in a
large-displacement analysis. By default, the detailed model change output is suppressed.
See Element and Contact Pair Removal and Reactivation for details
on model change operations.
Step module: OutputDiagnostic Print: toggle on Model Change
Requesting Detailed Printout of Problems with the Plasticity Algorithms
You can activate printout of element and integration point numbers for which the
plasticity algorithms have failed to converge during an iteration. This information is
useful for finding the place in the mesh and/or the plasticity model at which Abaqus is encountering material model difficulties. Modeling problems and material parameter
specification problems can be identified using this detailed printout. By default, this
printout is suppressed.
Step module: OutputDiagnostic Print: toggle on Plasticity
Requesting Output of Equilibrium Residuals
By default, equilibrium residuals during equilibrium iterations are output. You can
choose to suppress this output entirely, but it is not recommended; without the output
of equilibrium residuals, you cannot see the accuracy of the iteration process.
Step module: OutputDiagnostic Print: toggle on Residual
Requesting Solver Information
By default, information about the number of equations being solved and the number of
floating point operations is output for each iteration. You can request for this output
to be suppressed.
You can activate detailed printout of adaptive mesh smoothing in Abaqus/Standard. The output includes information about the magnitude of the maximum displacement and
the node and degree of freedom where the maximum displacement increment occurs during
each mesh sweep. It also provides the node numbers at which geometric feature changes
occur. By default, only a summary is output.
Adaptive mesh output to the message file is not supported in Abaqus/CAE.
Monitoring a Degree of Freedom in the Message File
You can write the current value of a specified point and degree of freedom to the
message file. This information can be used to monitor the progress of the solution. The
information will also be written in the status file (see below). You can control the
frequency at which the value is printed in the message file. The default frequency is 1
(or 10 in a direct cyclic analysis).
Degree of freedom monitoring does not apply to eigenvalue buckling prediction,
eigenfrequency extraction, or response spectrum procedures. For other linear
perturbation procedures output for the monitored degree of freedom is the base state
value.
The node and degree of freedom being monitored can be changed from step to step by
repeating the MONITOR option. The node and
degree of freedom specified in the last occurrence of this option in a step will be
used for that step.
Abaqus/CAE Usage
Step module: OutputDOF Monitor: Monitor a degree of freedom throughout the analysis, click Edit to select the point, Degree of freedom:dof, Print to the message file every N increments
In Abaqus/CAE only one point and degree of freedom can be monitored for an analysis; you cannot
change the monitor request from step to step.
The status file (job-name.sta) is a text
file that contains information about the progress of an analysis.
The Abaqus/Standard Status File
The Abaqus/Standard status file contains a single 80-character record for each increment and is updated
upon completion of each increment of an analysis. This record is written directly to
secondary storage immediately at the completion of the increment. Therefore, the status
file can be examined as the analysis job is executing, thus providing a monitor of the
progress of the analysis. Other than specifying that a degree-of-freedom variable be
monitored in the status file in Abaqus/Standard (as described below), the information written to the Abaqus/Standard status file cannot be controlled.
The Abaqus/Explicit Status File
In Abaqus/Explicit the status file (job-name.sta)
contains, by default, mass and inertial properties for the model, initial stable time
increment information, a synopsis of the progress of the analysis including total
accumulated CPU usage and the current time increment
size, and an estimate of the memory required to process each step. You can control
additional output including the total kinetic energy, the energy balance, the identifier
of the element with the smallest stable time increment, and the percent change in total
mass of the model due to mass scaling.
The frequency at which summary increments are written to the Abaqus/Explicit status file depends on the duration of the analysis in
CPU minutes and the amount of output specified in the
analysis. The following list provides general guidelines for when a summary increment will
be written to the status file.
Summary information will generally be written:
Each time restart information, field output to the output database, or results file
output is written.
Once per increment if the problem requires fewer than 20 increments.
20 times during the step for a short analysis (less than 40
CPU minutes).
Every 2 CPU minutes for an analysis longer than 40
CPU minutes.
A degree-of-freedom variable can be monitored in the status file while the analysis is
running. You can also write additional diagnostic information to the status file (see
Explicit Dynamic Analysis and Contact Diagnostics in an Abaqus/Explicit Analysis for details).
A portion of the diagnostic information in the status file,
including information for each summary increment, is also written to the output database
for use in Abaqus/CAE (for more information, see Requesting Output to the Output Database).
Errors that can be detected only while packaging the data for Abaqus/Explicit or during analysis are also written to the status file.
The PRINT option can appear only
once within a step definition.
Abaqus/CAE Usage
Step module: OutputDiagnostic Print
Requesting Kinetic Energy Output
By default, the kinetic energy for the model is written to the status file. This output
is written periodically throughout the step. You can choose to include or exclude the
kinetic energy output for each step.
Step module: OutputDiagnostic Print: toggle on Allke
Requesting Total Energy Output
By default, the energy balance is written periodically throughout the step. You can
choose to include or exclude the energy balance output for each step.
Step module: OutputDiagnostic Print: toggle on Etotal
Requesting Output of the Critical Element
By default, the number of the element with the current minimum stable time increment is
output to the status file. This output is written periodically throughout the step. You
can choose to include or exclude the critical element output for each step.
Step module: OutputDiagnostic Print: toggle on Crit. Elem.
Requesting Output of the Change in the Total Mass
You can write the percent change in total mass of the model due to mass scaling to the
status file for each step. This output is written periodically throughout the step. The
percent change in total mass is printed by default only if mass scaling is present in
the model.
Step module: OutputDiagnostic Print: toggle on Dmass
Monitoring a Degree of Freedom in the Status File
You can write the current value of a specified point and degree of freedom to the Abaqus/Standard status file. The value of the point and degree of freedom being monitored will appear
in the status file for every increment written during the analysis.
When a degree of freedom is monitored in the Abaqus/Standard status file, the same information is written to the message file (see above), but the
specified frequency has no effect on the output to the status file.
Degree of freedom monitoring does not apply to eigenvalue buckling prediction,
eigenfrequency extraction, or response spectrum procedures. For other linear perturbation
procedures output for the monitored degree of freedom is the base state value.
The node and degree of freedom being monitored can be changed from step to step by
repeating the MONITOR option. The node and
degree of freedom specified in the last occurrence of this option in a step will be used
for that step.
Abaqus/CAE Usage
Step module: OutputDOF Monitor: Monitor a degree of freedom throughout the analysis, click Edit to select the point, Degree of freedom:dof
In Abaqus/CAE only one point and degree of freedom can be monitored for an analysis; you cannot
change the monitor request from step to step.
Requesting Output in Multiple Steps
In general, output requests apply to the step in which they are given and to all subsequent
steps until they are respecified. However, output specifications for linear perturbation
steps (available only in Abaqus/Standard; see below and General and Perturbation Procedures) are treated
independently of output requests for general analysis steps and apply only to a continuous
sequence of linear perturbation steps.
Database output, printed output, and results file output are independent output modes in
Abaqus; therefore, changing the specification for one form of output does not affect the other
forms.
General Analysis Steps
The default output requests are used in the first general analysis step of an analysis
unless you redefine them. For subsequent general analysis steps, the definition of each
form of output from the previous general step is maintained unless you redefine it.
Linear Perturbation Steps
The default output requests are used in the first of any sequence of linear perturbation
steps unless they are redefined in that step. If a subsequent linear perturbation step is
defined without an intermediate general analysis step, the definition of each mode of
output from the previous perturbation step is maintained unless you redefine it. If an
intermediate general step is defined, the default output requests are again used in the
linear perturbation step unless they are redefined in that step.
Element Matrix Output in Abaqus/Standard
In Abaqus/Standard you can write element stiffness matrices and, if available, mass matrices for each step
to a file. For heat transfer elements the operator matrices are written if stiffness matrix
output is requested.
Element matrix output is available only for elements without internal nodes (unless those
nodes have no active degrees of freedom) and with no acoustic or internal degrees of
freedom. Examples of elements for which element matrix output is prohibited include
acoustic, pipe, elbow, frame, gap, and interface elements as well as axisymmetric elements
with Fourier modes. Element matrix output is not available for elements with coupled fields
such as coupled temperature-displacement elements and pore pressure elements. For
incompatible mode and hybrid elements, stiffness matrix output is prohibited while mass
matrix output is available. A substructure matrix output request is used to write a
substructure's reduced stiffness matrix, mass matrix, and load case vectors to a file (see
Generating Substructures).
Element matrix output cannot be requested in a mode-based dynamic analysis (response
spectrum, steady-state dynamic, modal dynamic, or random response). However, it can be
requested in the eigenfrequency extraction analysis that precedes the mode-based dynamic
analysis to output the mass and stiffness matrices.
The element matrices are written without the effects of nodal conditions; therefore,
boundary conditions, concentrated loads, and the effects of multi-point constraints are not
included in this output. The degrees of freedom are always in the global directions, even if
a local coordinate system (Transformed Coordinate Systems) has been
defined at nodes associated with the element.
You must select the element set for which output is requested. For models defined in terms
of an assembly of part instances (Assembly Definition), element
numbers written with element matrix output are internal numbers generated by Abaqus/Standard. A map between internal numbers and the original element numbers and part instance names
is provided in the data file.
Writing the Element Matrices to the Results File
By default, element matrix output records are written to the Abaqus/Standard results file. The record formats for the results file are described in Results File. The file can be written in binary or
ASCII format based on the file format you specify (see
Controlling the Format of the Results File in Abaqus/Standard above).
Element matrix output is not supported in Abaqus/CAE.
Writing the Element Matrices to a User-Defined File
You can write the element matrices to a user-defined file. The file name should not
include an extension; the extension .mtx will be added. (See Input Syntax Rules for the syntax
of user-specified file names.)
The format of the output file is compatible with the linear user element (see User-Defined Elements).
Input File Usage
ELEMENT MATRIX OUTPUT, ELSET=elset,
OUTPUT FILE=USER DEFINED, FILE NAME=output_file_name
Abaqus/CAE Usage
Element matrix output is not supported in Abaqus/CAE.
Writing the Element Matrices to the Data File
You can write the element matrix records to the Abaqus/Standard data file.
Element matrix output is not supported in Abaqus/CAE.
Controlling the Frequency of Element Matrix Output
You can control the frequency at which element matrix output will be written by
specifying an output frequency in increments. By default, the element matrices will be
output every increment (equivalent to an output frequency of 1). Specify an output
frequency of 0 to suppress output of the element matrices. Unless the output is
suppressed, the matrices will always be written at the last increment of a step.
Element matrix output is not supported in Abaqus/CAE.
Writing the Stiffness or Operator Matrix
You can choose to output the stiffness matrix (or operator matrix in heat transfer
elements). By default, the stiffness (operator) matrix is not output.
Element matrix output is not supported in Abaqus/CAE.
User-Defined Output Variables in Abaqus/Standard
In Abaqus/Standard output quantities can be defined as functions of any element integration point variable
listed in Abaqus/Standard Output Variable Identifiers by using user subroutine UVARM. Then, output variable
UVARMn can be
requested for output to the data file, the results file, or the output database.
User-Defined State Variables in Abaqus/Standard
In Abaqus/Standard you can allocate solution-dependent state variables and define them in user subroutines
defining material behavior, as well as user subroutines FRIC, UEL, and UINTER (see About User Subroutines and Utilities). Output
variable SDVn
can be requested for output of these state variables to the data file, the results file, or
the output database. For user-defined elements output variable
SDVn cannot be
requested for output to the output database.
Postprocessing with Abaqus/CAE
Abaqus/CAE provides interactive graphical postprocessing from the Abaqus output database file in the Visualization module (also licensed separately as Abaqus/Viewer). Capabilities include model and deformed shape plotting, contour plotting, vector
plotting, X–Y plotting, and animation.
Recovering Additional Results Output from Restart Data in Abaqus/Standard
Data needed for restart in Abaqus/Standard are contained in several files that are generated when you request that restart data be
written for an analysis: the restart (.res), analysis database
(.mdl and .stt), part
(.prt), and output database (.odb) files. Restarting an Analysis describes the
writing of restart data in more detail.
In Abaqus/Standard you can extract output from the restart data and write it to new data
(.dat), results (.fil), and output database
(.odb) files using a postprocessing analysis procedure. If the
original analysis included user subroutines, the postprocessing analysis procedure requires
the specification of the user subroutines. The data,
results, and output database file output requests are defined as described in Output to the Data and Results Files and Output to the Output Database. The output requests should be defined exactly as they would be in an analysis,
except that:
The output frequency specification has no meaning and is, therefore, ignored (unless
you are recovering additional output from a previous direct cyclic or low-cycle fatigue
analysis). Instead, you specify each increment at which output is to be generated in the
postprocessing procedure definition.
No default output is provided to the output database. Furthermore, model information,
such as boundary conditions, is not written to the output database.
Element set energy information cannot be recovered since it is not written to the
restart file.
Output is not available for procedures that do not support restart; for example, linear
perturbation procedures.
The element sets and node sets that are defined for the analysis can be used for defining
output sets during the postprocessing procedure. Additional sets can also be defined for the
postprocessing procedure. You specify the step number in the restart file from which output
is required. You cannot obtain results at the beginning of a step (see below).
When the POST OUTPUT option is used, it
must appear as the first option in the input file. No data lines from the analysis input
file are required. This option can be repeated as often as necessary to obtain further
output. Since POST OUTPUT is a purely
postprocessing procedure, analysis options must not appear in the input file.
Abaqus/CAE Usage
Postprocessing of restart data is not supported in Abaqus/CAE.
Recovering Additional Output from a Direct Cyclic Analysis
If you use this postprocessing technique to recover additional output from a previous
direct cyclic analysis (see Direct Cyclic Analysis), you must
specify the iteration number in the restart file from which output is required instead of
the increment. If temperatures (or predefined field variables) are read from a results
(.fil) file in the original direct cyclic analysis, the same
temperatures (or predefined field variables) must be read into the postprocessing
analysis. This specification is needed to recover thermal strains at each time increment
in the original direct cyclic analysis since the results file is not stored in the restart
analysis database.
Input File Usage
POST OUTPUT, STEP=step_number, ITERATION=iteration_number
There are no data lines associated with this option if the
ITERATION parameter is
specified.
Abaqus/CAE Usage
Postprocessing of restart data is not supported in Abaqus/CAE.
Recovering Additional Output from a Low-Cycle Fatigue Analysis
If you use this postprocessing technique to recover additional output from a previous
low-cycle fatigue analysis (see Low-Cycle Fatigue Analysis Using the Direct Cyclic Approach), you must
specify the cycle number in the restart file from which output is required instead of the
increment. If temperatures (or predefined field variables) are read from a results
(.fil) file in the original low-cycle fatigue analysis, the same
temperatures (or predefined field variables) must be read into the postprocessing
analysis. This specification is needed to recover thermal strains at each time increment
in the original low-cycle fatigue analysis since the results file is not stored in the
restart analysis database.
There are no data lines associated with this option if the
CYCLE parameter is specified.
Abaqus/CAE Usage
Postprocessing of restart data is not supported in Abaqus/CAE.
Example
A job can be submitted using the following input file. The analysis for which restart
data were written must be specified when you submit the job (using the
oldjob parameter of the Abaqus execution procedure). This example creates a new data (.dat) file
containing tabular data. The first two tables will contain data from increments 5 and 10
of Step 1 and will give the reaction forces of the nodes in the set
CLAMP, which was defined when the analysis was run. The
next table will contain data from increment 3 of Step 2 and will give displacements from
the new node set TIP that is defined in this
postprocessing analysis.
The following example input file recovers additional output from a previous direct cyclic
analysis and creates a new output database (.odb) file, which
contains the stress and strain for the elements in the set
ELIST from each increment in Iteration 5 of Step 1,
followed by data from each increment in Iteration 10 of Step 1:
The following example input file recovers additional output from a previous low-cycle
fatigue analysis and creates a new output database (.odb) file, which
contains the stress and strain for the elements in the set
ELIST from each increment in Cycle 5 of Step 1,
followed by data from each increment in Cycle 10 of Step 1: