About Fracture Mechanics

Abaqus/Standard provides several methods for performing fracture mechanics studies.

The following methods are available:

Onset of cracking

The onset of cracking can be studied in quasi-static problems by using contour integrals (Contour Integral Evaluation). The J-integral, the C t -integral (for creep), the stress intensity factors for both homogeneous materials and interfacial cracks, the crack propagation direction, and the T-stress are calculated by Abaqus/Standard. Contour integrals can be used in two- or three-dimensional problems. In these types of problems, focused meshes are generally required and the propagation of a crack is not studied.

Crack propagation

The crack propagation capability allows quasi-static, including low-cycle fatigue, crack growth along predefined paths to be studied (Crack Propagation Analysis). Cracks debond along user-defined surfaces. Several crack propagation criteria are available, and multiple cracks can be included in the analysis. Contour integrals can be requested in crack propagation problems.

Line spring elements

Part-through cracks in shells can be modeled inexpensively by using line spring elements in a static procedure, as explained in Line Spring Elements for Modeling Part-through Cracks in Shells.

Extended finite element method (XFEM)

XFEM models a crack as an enriched feature by adding degrees of freedom in elements with special displacement functions (Modeling Discontinuities as an Enriched Feature Using the Extended Finite Element Method). XFEM does not require the mesh to match the geometry of the discontinuities. It can be used to simulate initiation and propagation of a discrete crack along an arbitrary, solution-dependent path without the requirement of remeshing. You can also use XFEM to perform contour integral evaluation for an arbitrary stationary surface crack without the need to define a conforming mesh around the crack tip.