Build Cross-section in Abaqus and Export to VABS#

Brief Instruction#

Overall, the process is similar to creating a meshed beam cross-section part in Abaqus.

  • Part:

    • Modeling space: 2D planar

    • Type: Deformable

    • Base feature: Shell

  • Property:

    • Material: Any

    • Section: Composite layup (Solid, Homogeneous)

  • Mesh: Any

Write the Abaqus model to an INP file.

Convert the INP file to a VABS input file using the command:

python -m sgio convert <filename>.inp <filename>.sg -ff abaqus -tf vabs

Detailed Instruction#

Part module#

As a cross-section of a slender structure, it is natural to create a “Deformable” “Shell” part in the “2D Planar” modeling space.

../_images/abaqus_cs_create_part.png

Composite structures can have different materials in different regions. A useful tip is to create a base shape, such as a circle, large enough to cover the entire cross-section. Then, use the “Partition Face” tool to divide the base shape into regions.

../_images/abaqus_cs_partition_face.png

Property#

Any type of material can be used for the cross-section, such as isotropic, engineering constants, or orthotropic. VABS requires local orientation data and allows additional in-plane rotations (fiber angle) for each layer. Hence, it is required to use the “Composite Layup” section type. Here are instructions for setting up a “Composite Layup” section:

  • Each section contains only one ply.

  • Layer orientation is defined by assigning the local \(y\) axis, while the local \(x\) axis is always normal to the cross-sectional plane. For a composite layer, the local \(y\) axis is usually set to be tangent to a base line.

  • To set the fiber angle for each layer, use the column “Rotation Angle”.

../_images/abaqus_cs_comp_section.png

It is okay to use the “Composite Layup” section for all materials. However, if a material is isotropic and no local orientation and fiber angle are needed, then it is also acceptable to use the “Solid” section.

../_images/abaqus_cs_solid_section.png

Mesh#

There is no restriction on meshing.

../_images/abaqus_cs_mesh.png

File export#

Create a job and write the model to an INP file. Then use the command below to convert the INP file to a VABS input file:

python -m sgio convert <filename>.inp <filename>.sg -ff abaqus -tf vabs

By default, the Timoshenko beam model will be used. To use the Euler-Bernoulli beam model, add the option -m bm1:

python -m sgio convert <filename>.inp <filename>.sg -ff abaqus -tf vabs -m bm1

To see help messages, use the command:

python -m sgio convert -h