abaqus tutorial assistant 2017
get started with Abaqus/CAE
introduction
getting started with abaqus
how to use this guide
new Abaqus users
introduction about A Python script
Finite Elements and Rigid Bodies
The use of continuum (solid) elements, shell elements, and beam elements
Linear dynamic
Nonlinearity
Nonlinear dynamic analyses
material nonlinearity introduced in Materials
Multiple Step Analysis
Contact
introduction about Abaqus/CAE plug-in scripts
experienced Abaqus users
Creating and Analyzing a Simple Model in Abaqus/CAE
Using Additional Techniques to Create and Analyze a Model in Abaqus/CAE
Viewing the Output from Your Analysis
Abaqus documentation
other guides
check exmaple
Abaqus Verification Guide
Abaqus Theory Guide
Abaqus Keywords Guide
Abaqus Example Problems Guide
the basic guides
Abaqus Analysis Guide
Abaqus Constraints Guide
Abaqus Elements Guide
Abaqus Execution Guide
Abaqus Interactions Guide
Abaqus Introduction & Spatial Modeling Guide
Abaqus Materials Guide
Abaqus Output Guide
Abaqus Prescribed Conditions Guide
getting help
change default local documentation to online documentation
open
D:\Program Files\Dassault Systemes\SimulationServices\V6R2017x\win_b64\SMA\site\custom_v6.env
change
doc_root="file:///C:/Program Files/Dassault Systemes/SIMULIA2017doc/English"
to
doc_root="https://abaqus-docs.mit.edu/2017/English"
color
searched by myself online
1gists of content
2gists of content
catalog
support
A quick review of the finite element method
Obtaining nodal displacements using implicit methods
Implicit finite element methods require that a system of equations is solved at the end of each solution increment.
Stress wave propagation illustrated
how forces propagate through a model when using the explicit dynamics method
Abaqus Basics
VIM
fold:zc
unfold:zo
Preprocessing, simulation, and postprocessing
Components of an Abaqus analysis model
loads and boundary conditions
discretized geometry,
element section properties
material data
numerical singularity” or “zero pivot” warning message during a static stress analysis, you should check whether all or part of your model lacks constraints against rigid body translations or rotations.
analysis type
output requests
the Abaqus input file for a simple analysis can be created directly using a text editor.
Introduction to Abaqus/CAE
Components of the main window
What is a module?
Interation
Abaqus/CAE does not recognize mechanical contact between part instances or regions of an assembly unless that contact is specified in the Interaction module
Assembly
Assembly module
to create instances of your parts
to create instances of other models
to position the instances relative to each other in a global coordinate system, thus creating an assembly
An Abaqus model contains only one assembly
part
it exists in its own coordinate system, independent of other parts in the model
functions of all bars and areas
Example: creating a model of an overhead hoist
the Python scripts
1.From the main menu bar, select File->Run Script.
2.Choose the file from the list of available scripts (.py file)
units
creating part
select the Delete tool
In the prompt area, select Constraints as the scope of the operation
the Sketcher Options tool
You should always save your model database at regular intervals
Defining and assigning section properties
use the command line interface (CLI) in Abaqus/CAE as a simple calculator
type pi0.005*2/4.0
Defining the assembly
parts
instances
one assembly
Configuring your analysis
Creating an analysis step
general analysis steps
linear perturbation steps
Applying boundary conditions and loads to the model
All the mechanical boundary conditions specified in the Initial step must have zero magnitudes
Meshing the model
The Mesh module functionality is available only through
menu bar items
toolbox icons
Basic meshing
two-stage operation
- mesh the part instance
Assigning an Abaqus element type
who comes first does not matter
- seed the edges of the part instance
display the node and element numbers
View->Part Display Options from the main menu bar
Toggle on Show node labels and Show element labels in the Mesh tabbed page of the Part Display Options dialog box that appears
Creating an analysis job
job name = output file name
Postprocessing
Postprocessing: overhead hoist
Viewport->Viewport Annotation Options
Customizing an undeformed shape plot
Options->Common->Labels or 
Displaying and customizing a deformed shape plot
view->specify->rotation angles->total rotation from
Plot->Deformed Shape or 
Options->Common->Basic->Deformation Scale Factor or
Plot->Allow Multiple Plot States or 
Options->Superimpose or 
Checking the model with Abaqus/CAE
View->ODB Display Options->Entity Display->Show bounday conditions.
Generating tabular data reports
Report->Field Output
generate rpt file
click to edit
copy to windows clipboard
"*y
windows clipboard to vim
"*p
Using Continuum Elements
Element formulation and integration
Full integration
Reduced integration
An FE solver computes displacement and force results at the element nodes
Unlike displacements and forces, strains and stresses are not computed at the nodes. They are computed at specific “integration points” within the element.
The calculated stresses and strains are then extrapolated out to the nodes.
Incompatible mode elements
high accuracy at a low cost
best choice for most general stress/displacement simulations, except in large-displacement simulations involving very large strains and in some types of contact analyses
However, care must be taken to ensure that the element distortions are small, which may be difficult when meshing complex geometries;
therefore, you should again consider using the reduced-integration, quadratic elements in models with such geometries because they show much less sensitivity to mesh distortion.
moving
less sensitive, but still need to consider it
sensitive
sensitivity to mesh distortion
Selecting continuum elements
recommendations
example: Lug
Prescribing boundary conditions and applied loads
In Abaqus/CAE boundary conditions are applied to geometric regions of a part rather than to the finite element mesh itself. This association between boundary conditions and part geometry makes it very easy to vary the mesh without having to respecify the boundary conditions. The same holds true for load definitions.
Partitioning
used for the purposes of defining material boundaries
indicating the location of loads and constraints
refining the mesh
Designing the mesh: partitioning and creating the mesh
green
a region can be meshed using structured methods
Yellow
a region can be meshed using sweep methods
Pink
a region can be meshed using the free method.
Tan
can be meshed using the bottom-up method
Orange
a region cannot be meshed using the default element shape assignment and must be partitioned further.
To manipulate the view using the 3D compass:
Click and drag one of the straight axes of the 3D compass to pan along an axis.
Click and drag any of the quarter-circular faces on the 3D compass to pan along a plane.
Click and drag one of the three arcs along the perimeter of the 3D compass to rotate the model about the axis that is perpendicular to the plane containing the arc.
Click and drag the free rotation handle (the point at the top of the 3D compass) to rotate the model freely about its pivot point.
Click the label for any of the axes on the 3D compass to select a predefined view (the selected axis is perpendicular to the plane of the viewport).
Double-click anywhere on the 3D compass to specify a view.
View->Specify->Viewpoint
Viewpoint
Up vector
Postprocessing—visualizing the results
Visible edges
Options->Common->Visible Edges
Render style
wireframe , hidden line , filled , and shaded
Contour plots
Result->Field Output
Contour Options 
Displaying contour results on interior surfaces
Tools->View Cut or 
Maximum and minimum values
Viewport->Viewport Annotation Options->Legend->Show min/max values
Displaying a subset of the model
Results Tree->Display Groups
Displaying a free body cut
to view the resultant forces and moments transmitted across a selected surface of a model
Tools->Free Body Cut->Manager
Generating tabular data reports for subsets of the model
Display Groups
Report->Field Output.
Save Selection As
abaqus experience
error
2D model use continuum element
Part: 2D Planar Shell
Section: choose Solid Homogenous
not Generalized plane strain
create coordinate system
Result->Option->Transformation->User-specified
Using Shell Elements
Use shell elements to model structures
the stresses in the thickness direction are negligible
one dimension (the thickness) is significantly smaller than the other dimensions
The degrees of freedom for the shell are associated with the reference surface.
To verify that the local material directions have been assigned correctly
Tools->Query
Example: skew plate
Creating the mesh and defining a job
Choosing a shell element
1/10 (surface scale not the element scale) use shell
high 1/15 thick shell
low 1/15 thin shell
large strain or small strain
large rotations
Finite-strain shell elements
large strain large rotation
though large strain, approximately less than 10% thickness change
Small-strain shell elements
small strain large rotation
The change in thickness with deformation is ignored in these elements
Thickness change is considered only in geometrically nonlinear analyses
For conventional shells
the strain results only from the Poisson’s effect
For continuum shells
the stress in the thickness direction may not be zero
may cause additional strain beyond that due to Poisson’s effect
stress in the thickness direction is zero
Reduced integration
used with first-order (linear) elements, hourglass control is required
The second-order reduced-integration elements
generally do not have the same difficulty and are recommended in cases when the solution is expected to be smooth
must check if hourglassing is occurring; if it is, a finer mesh may be required or concentrated loads must be distributed over multiple nodes.
First-order elements
recommended when large strains or very high strain gradients are expected
Because the strain is typically considered small if it is less than 4 or 5%, a strain of 0.8% is well within the appropriate range to be modeled with S8R5 elements.
Using Beam Elements
assumption
For beam theory to produce acceptable results, the cross-section dimensions should be less than 1/10 of the structure's typical axial dimension
Shear deformation
model shear
These elements can provide useful results as long as the cross-section dimensions are less than 1/10 of the typical axial dimensions of the structure, which is generally considered to be the limit of the applicability of beam theory
not model shear
These elements assume that shear deformations are negligible. Generally, if the cross-section dimensions are less than 1/15 of the typical axial dimensions of the structure, this assumption is valid.
if the beam cross-section does not remain plane under bending deformation, beam theory is not adequate to model the deformation.
Torsional response—warping
The warping calculation assumes that the warping displacements are small.
example
part
A datum plane, parallel to one of the trusses.
The orientation of the sketch plane will be defined using a datum axis.
see a graphical representation of the beam profile
View->Part Display Options and toggle on Render beam profiles
Linear Dynamics
Example
Modifications to the model
eigenvalue extraction methods
The Lanczos method
The subspace iteration method
generally faster when a large number of eigenmodes is required for a system with many degrees of freedom
faster when only a few (less than 20) eigenmodes are needed
Results
There is no point in extracting modes whose period is substantially smaller than the time increment used. Conversely, the time increment must be capable of resolving the highest frequencies of interest.
Interpolation or Nodel position
add "Coord" at the .inp file
Postprocessing
Determining the peak pull-out force
Plot multiple curves
Position the grid
Position the legend
Double-click the plot to open the Chart Options dialog box
click mouse button 3 on History Output for the output database named DynCrane.odb. From the menu that appears, select Filter.
enter *RF1* to restrict the history output
Double-click the legend to open the Chart Legend Options dialog box
To modify the curve styles
Query the X–Y plot
check points on plot
Tools->Query->Probe Values
Nonlinearity
Including nonlinearity in an Abaqus analysis
Geometric nonlinearity
Local directions
For shell, beam, and truss elements the local material directions always rotate with the deformation.
For solid elements the local material directions rotate with the deformation only if the elements refer to nondefault local material directions; otherwise, the default local material directions remain constant throughout the analysis.
Unit
1 m
1000 mm
E 30e9 Pa
30e3 N/mm2
Load 2e4 Pa
2e-2 N/mm2
Example: nonlinear skew plate
Job diagnostics
Do not need more iterations
largest correction to displacement < 0.01 largest increment of displacement
the largest residual force < 0.05time average force
despite the first iteration
as thery are equal
Postprocessing
show frames
Main menu bar: Result->Step/Frame
Frame selector: Up right corner
nodal/node query still use the global system, while .rpt result could be changed by Main menu bar -> Result -> Option -> Transformation
so that to use CPE8R
have not read
Nonlinear Explicit Dynamics
Materials
Multiple step Analysis
General analysis procedures
Linear perturbation steps
The starting condition for each general step is the ending condition of the previous general step. Thus, the model's response evolves during a sequence of general steps in a simulation.
Linear perturbation steps (available only in Abaqus/Standard) calculate the linear response of the structure to a perturbation load. The response is reported relative to the base state defined by the condition of the model at the end of the last general step.
Restart
Restart files can be used to continue an interrupted analysis or to add additional load history to the simulation.
Contact
Contact algorithm
contact pair
general contact
Surface
Surfaces on continuum elements
Surfaces on structural, surface, and rigid elements
double-sided surfaces
edge-based surfaces
single-sided surfaces
node-based surfaces
Rigid surfaces
Small sliding is not available for general contact.
2D beam orientation
abaqus findkeyword
abaqus fetch
files will be stored at file temp
click to edit
SF/SM better than NFORCE
use body cut
If you have a large job needing lots of memory
change scratch file
job->edit->general->scratch directory
Save Session
delete the old file. Otherwise it is going to append to the old file
the Selection toolbar
tools->option->view manipulation->solidworks
view->graphics options->blackground
view->toolbar->views->1 2 3 4 save specific views
coggle it
ctrl+alt+c
change color
shift
create cross link
ctrl +
font size
tie
position tolerance
if both faces are relatively regular
shell
sp1 neg
sp3 pos
1-, 2-, 3-axes
cylindrical
R,theta,Z
spherical
R, theta,phi
specify distance 0.005
if both faces are not so regular
corrugated steel pipe and grout or CC
specify distance larger
mesh control
Algorithm
use mapped tri meshing on boundary faces where appropriate
when two faces tie, it is better to turn it on, so both faces have nodes at the same point.
when at some parts the meshing is not as you expect, turn it off
like, at the boundary of the soil, you want it to be only one seed, but it is meshed into 4
move slave parts to master parts even though the fixed boundaries are on slave parts
shell obtain results at middle section
integration=5
field output->Output at shell, beam, and ....->Specify->1,2,3,4,5
Abaqus python scripts
5 ways to choose geometry