20.1 Modeling fracture mechanics
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You can study the onset of cracking in a quasi-static model by selecting regions from your model that will be used to compute contour integral estimates. During the analysis ABAQUS/Standard writes the values of the contour integrals to the output database as history output. For a detailed description of contour integrals, see Contour integral evaluation, Section 11.4.2 of the ABAQUS Analysis User's Manual. This section describes how you define a crack in ABAQUS/CAE. The following topics are covered:
An overview of contour integral analysis, Section 20.1.1
Defining the crack front, Section 20.1.2
Defining the crack tip or crack line, Section 20.1.3
Defining the crack extension direction, Section 20.1.4
Controlling the singularity at the crack tip for a small-strain analysis, Section 20.1.5
Contour integral output, Section 20.1.6
Meshing the crack region and assigning elements, Section 20.1.7
What is a seam?, Section 20.1.8
Creating a seam, Section 20.1.9
Controlling the singularity at the crack tip, Section 20.1.10
Defining data for contour integrals, Section 20.1.11
Modifying data for contour integrals, Section 20.1.12
Requesting contour integral output, Section 20.1.13