KCALC

KCALC, KPLAN, MAT, KCSYM, KLOCPR
Calculates stress intensity factors in fracture mechanics analyses.

POST1: Special Purpose
Valid Products: Pro | Premium | Enterprise | PrepPost | Solver | AS add-on

KPLAN

Key to indicate stress state for calculation of stress intensity factors:

0

 — 

Plane strain and axisymmetric condition (default).

1

 — 

Plane stress condition.

MAT

Material number used in the extrapolation (defaults to 1).

KCSYM

Symmetry key:

0 or 1 

 — 

Half-crack model with symmetry boundary conditions (DSYM]) in the crack-tip coordinate system. KII = KIII = 0. Three nodes are required on the path.

2

 — 

Like 1 except with antisymmetric boundary conditions (KI = 0).

3

 — 

Full-crack model (both faces). Five nodes are required on the path (one at the tip and two on each face).

KLOCPR

Local displacements print key:

0

 — 

Do not print local crack-tip displacements.

1

 — 

Print local displacements used in the extrapolation technique.

Notes

Calculates the stress intensity factors (KI, KII, and KIII) associated with homogeneous isotropic linear elastic fracture mechanics.

A displacement extrapolation method is used in the calculation. (See POST1 - Crack Analysis (KCALC) in the Feature Archive.) This method assumes that the displacement calculations are for the plane strain state. If the displacement calculations are performed using a plane stress formulation, the calculation of the stress intensity factors can be converted to the plane strain state by using KPLAN = 1.

The program uses minor Poisson's ratio (MP,NUXY) for the stress intensity factor calculation.

Issue the PATH and PPATH commands to define a path with the crack face nodes (NODE1 at the crack tip, NODE2 and NODE3 on one face, NODE4 and NODE5 on the other (optional) face).

A crack-tip coordinate system, having x parallel to the crack face (and perpendicular to the crack front) and y perpendicular to the crack face, must be the active RSYS and CSYS before KCALC is issued.