Transferring results between explicit dynamic procedures with nonlinear
geometry
Elements tested
- B21
- B22
- B31
- B32
- C3D4
- C3D4H
- C3D5
- C3D6
- C3D8
- C3D8I
- C3D8R
- C3D10M
- CAX3
- CAX4R
- CAX6M
- CPE3
- CPE4R
- CPE6M
- CPS3
- CPS4R
- CPS6M
- M3D3
- M3D4R
- M3D4
- S3R
- S3RS
- S4
- S4R
- S4RS
- S4RSW
Problem description
The verification tests outlined in this section are carried out for all
element types listed. The finite element model consists of elements subjected
to increasing tensile loads. The first analysis consists of a single explicit
dynamic step. The results from the end of this step of the analysis are
transferred to a second analysis, where further tensile loading is applied. The
tests are performed for all combinations of the import capability. The results
at the end of the second analysis should be identical to the results at the end
of the first analysis when the material state is imported and the reference
configuration is not updated. Elements are modeled with a variety of different
constitutive models, including isotropic elasticity; anisotropic elasticity;
lamina elasticity; orthotropic elasticity; orthotropic elasticity with
engineering constants; hyperelasticity with Marlow, Arruda-Boyce, and
polynomial potentials; hyperfoams; and equation of state. Hyperelastic models
are used in combination with viscoelasticity and Mullins effect considerations.
Modeling of inelastic effects includes plasticity and damage with several
different initial and evolution criteria.
Results and discussion
The results from the import analysis in which the material state is imported
and the reference configuration is not updated are identical to the results
from the end of the first analysis. In all cases when the reference
configuration is updated, the stresses, elastic strains, and equivalent plastic
strains are continuous during the transfer from the first analysis to the
second analysis. The displacements, strains, and energy quantities such as the
recoverable strain energy are continuous across the two analyses when the
reference configuration is not updated. At the beginning of the second
Abaqus/Explicit
analysis, strains start from zero if the reference configuration is updated;
the elastic strains, stresses, and equivalent plastic strains are set to zero
if the material state is not imported.
The input file names describe the analysis procedure, the material type modeled, and the values
of the options specified on import.
The first two characters indicate that the results are always transferred
from one
Abaqus/Explicit
analysis to another
Abaqus/Explicit
analysis. The third character, which is a number, indicates the analysis stage:
1 for the original analysis, and 2 for the first import analysis.
The first
Abaqus/Explicit
analysis files follow the format xx1_material.inp;
the second
Abaqus/Explicit
analysis files follow the format
xx2_material_update_state.inp,
where material indicates the material type used in
the analysis and update and
state indicate the value of these parameters: y for
yes and n for no.
Transferring results between explicit dynamic procedures with linear
geometry
Elements tested
- B21
- B22
- B31
- B32
- C3D4
- C3D4H
- C3D5
- C3D6
- C3D8
- C3D8I
- C3D8R
- C3D10M
- CAX3
- CAX4R
- CAX6M
- CPE3
- CPE4R
- CPE6M
- CPS3
- CPS4R
- CPS6M
- M3D3
- M3D4R
- M3D4
- S3R
- S3RS
- S4
- S4R
- S4RS
- S4RSW
Problem description
The verification tests outlined in this section are carried out for all
element types listed. The finite element model consists of elements subjected
to increasing tensile loads. The first analysis consists of a single explicit
dynamic step. The results from the end of this step of the analysis are
transferred to a second analysis, where further tensile loading is applied. The
tests are performed for both material state settings of the import capability.
The results at the end of the second analysis should be identical to the
results at the end of the first analysis when the material state is imported.
Elements are modeled with a variety of different constitutive models, including
isotropic elasticity, anisotropic elasticity, lamina elasticity, orthotropic
elasticity, and orthotropic elasticity with engineering constants.
Results and discussion
The results from the import analysis with the material state imported are
identical to the results from the end of the first analysis. In all cases when
the material state is imported, the stresses are continuous during the transfer
from the first analysis to the second analysis. The displacements strains and
energy quantities are continuous across the two analyses. At the beginning of
the second
Abaqus/Explicit
analysis, stresses are set to zero if the material state is not imported.
Transferring temperatures from an explicit dynamic procedure
Elements tested
- C3D4T
- C3D6T
- C3D8RT
- C3D8T
- C3D10MT
- CAX3T
- CAX4RT
- CAX6MT
- CPE3T
- CPE4RT
- CPE6MT
- CPS3T
- CPS4RT
- CPS6MT
Problem description
The verification tests outlined in this section are carried out for all
element types listed. The finite element model consists of elements subjected
to tensile and thermal loads. The first analysis consists of a single fully
coupled thermal-stress step. The results from the end of this step of the
analysis are transferred to a second analysis, where further tensile loading is
applied. The tests are performed with the material state imported and the
reference configuration updated and not updated. The results at the end of the
second analysis should be identical to the results at the end of the first
analysis when the material state is imported and the referenced configuration
is not updated. Elements are modeled with a variety of different constitutive
models, including isotropic elasticity, anisotropic elasticity, lamina
elasticity, orthotropic elasticity, and orthotropic elasticity with engineering
constants. The thermal properties of the material are taken to be isotropic.
Results and discussion
Results at the end of the second analysis are identical when the material
state is imported and the referenced configuration is not updated. When the
material state is imported and the reference configuration is updated, the
results are identical for the stresses; the thermal strains and total strains
differ due to the updated reference configuration.
Transferring acoustic results
Elements tested
- AC2D3
- AC2D4R
- AC3D4
- AC3D6
- AC3D8R
Problem description
The acoustic elements are subjected to a linearly increasing pressure
loading. Since acoustic elements have no material state, importing the material
state has no effect. Acoustic elements have pressure degrees of freedom only;
thus, if the reference configuration is updated, the pressure values will be
imported. If not, they will be set to zero.
Results and discussion
The import analysis is verified by comparing the results from the zero
increment of the imported analysis to the last increment of the previous
analysis.
Transferring contact conditions
Elements tested
Problem description
The verification tests in this section consist of analyses involving contact
with analytical rigid surfaces, surface contact, and edge contact. The results
from the end of the first step of the analyses are transferred to a second
analysis. The tests are performed with the material state imported and the
reference configuration updated and not updated.
The material model used for all the tests is isotropic linear elasticity,
together with Mises plasticity.
Results and discussion
The results at the beginning of the import analysis with the material state imported and the
reference configuration not updated are identical to the results at the end of the
original analysis. When the material state is imported and the reference configuration is
updated, the results for the two analyses are identical for the contact stresses; the
values for the relative slip of the surfaces differ due to the updated reference
configuration.
Transferring rebar layers and embedded elements
Elements tested
Problem description
The tests outlined in this section verify the accuracy of the transfer of
rebar layers and embedded elements from one
Abaqus/Explicit
analysis to another
Abaqus/Explicit
analysis. The tests are performed for all element types listed.
The tests involve elements with rebar layers or embedded elements subjected
to loading over two explicit dynamic steps in the first analysis. The results
from the end of the first step are then transferred to another
Abaqus/Explicit
dynamic import analysis. In addition to the imported elements, new elements
with rebar layers or embedded elements are defined in the import analysis.
These new elements are identical to the initial element definitions of the
imported elements in the original analysis. During the import analysis, the
imported elements and the newly defined elements are subjected to loads such
that the final loads are identical to those applied at the end of the second
step in the original analysis. The import analysis is performed with the
material state imported and the reference configuration updated and not
updated.
Results and discussion
The results for the two sets of elements in the import analysis—that is, the
newly defined elements and the imported elements—are identical at the end of
the analysis when the material state is imported and the reference
configuration is not updated. In addition, these results are identical to the
results at the end of the second step of the original analysis. These tests
demonstrate that appropriate quantities in the rebar layer and embedded
elements—such as the stresses, rebar orientations, strains, etc.—are
transferred accurately from one
Abaqus/Explicit
analysis to another. The only difference in the results at the end of the
import analysis when the reference configuration is updated compared to the
results when the reference configuration is not updated is in the kinematic
quantities such as the total strains, rebar rotations, etc. When the reference
configuration is updated in the import analysis, the total strains and the
rebar rotations at the beginning of the import analysis are set to zero; when
the reference configuration is not updated, the total strains and the rebar
rotations are continuous across the transfer from one analysis to another.
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