A Fracture analysis does not support adaptive mesh refinement.

For Arbitrary Crack, Semi-Elliptical Crack, Elliptical Crack, Ring Crack Corner Crack, Edge Crack, Through Crack, and Cylindrical Crack objects, crack meshing requires that the base mesh is a quadratic tetrahedron mesh. Linear elements may exist farther away from the buffer zone on the same body to which these cracks are scoped.

Only 3D analyses support semi-elliptical, elliptical, ring, and arbitrary cracks.

You can scope a Semi-Elliptical Crack, Elliptical Crack, Ring Crack, Corner Crack, Edge Crack, Through Crack, or Cylindrical Crack to one solid body only.

You should define Semi-Elliptical cracks on the surfaces of a solid body only, and the crack cannot span more than one face.

When the crack dimensions of an Elliptical Crack or a Ring Crack intersect with the free surfaces of the solid body, the application only supports the Tetrahedrons option of the Mesh Method property.

The Stiffness Behavior property of the geometry scoped to a Arbitrary Crack, Semi-Elliptical Crack, Elliptical Crack, Ring Crack, Corner Crack, Edge Crack, Through Crack, or Cylindrical Crack must be set to Flexible.

You can scope an Arbitrary Crack to one solid body only. And, you can only scope the Crack Surface property of the crack to a single surface body.

The scoped crack front nodal selection of the Pre-Meshed Crack object must exist in geometries with a flexible stiffness behavior definition.

It is not recommended that you specify a Part Transformation on a body that includes an Arbitrary Crack. This could lead to the application detecting an incorrect extension direction for the crack front nodes.

Arbitrary Cracks can only be meshed with the Tetrahedrons Mesh Method (Mesh Method set to Tetrahedrons).

Fracture parameter computations based on the VCCT technique are only supported for lower order crack mesh. Hence, VCCT based fracture parameter computations are only supported for Pre-Meshed Crack object.

In order to retain restart points when the Fracture property (Analysis Settings > Fracture Controls), is set to On, you must set the Generate Restart Points property (Analysis Settings > Restart Controls) to Manual.

Solution restarts are not supported if you are computing fracture parameters for SMART Crack Growth.

Analytical crack or arbitrary crack top and bottom face nodes are not connected through any constraint equation. Therefore, the nodes of the top face can penetrate the bottom face or vice versa based on the applied loads and constraints. In these scenarios, you may need to create a constraint equation between crack faces for the solution using the Commands (APDL) object.

The graphical view of a Semi-Elliptical Crack, Elliptical Crack, Ring Crack, Corner Crack, Edge Crack, Through Crack, or Cylindrical Crack may differ from the generated mesh. For more information, see the section on Cracks.

The Arbitrary Crack, Semi-Elliptical Crack, Elliptical Crack, Ring Crack, Corner Crack, Edge Crack, Through Crack, or Cylindrical Crack objects are not supported in combination with the following features:

Interpolated displacements for the facets in a surface construction object may fail to demonstrate the proper deformation of a Semi-Elliptical crack. For more information, see Surface Displays and Fracture.

In order to use the Fracture Tool to extract the fracture results and probe results from the results file of another analysis using the Read Result Files option, it is necessary that the meshes from both systems, including the crack mesh, match.

Fracture parameter calculations based on domain integrations such as SIFs, J-integral, or Material Force are not supported when contact elements exist inside the domain. The calculations may become path-dependent unless the contact pressure is negligible.

If you have a Hyperelastic material assigned in the analysis, only Material Force fracture results are supported.