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*INITIAL STRAIN INCREASE

Keyword type: step

This option is used to define an increase of initial strains. The values are
added to the initial strains already present in the model. The use of this
option requires the previous use of *INITIAL
CONDITIONS, TYPE=PLASTIC STRAIN or *MODEL
CHANGE, TYPE=ELEMENT, ADD or *MODEL
CHANGE, TYPE=ELEMENT, ADD=STRAIN FREE.

The resulting initial strain components are subtracted from the
strain components computed from the displacement field. If thermal strains are
relevant they are additionally subtracted. The resulting strain is used to
compute the stress and tangent stiffness matrix using the appropriate
constitutive equations.

Please note that the strains have to be provided in the
GLOBAL (rectangular) coordinate system, no matter whether an *ORIENTATION card
or *TRANSFORM card applies to the corresponding element.

First line:

Following line:

- Element number.
- Integration point number.
- Value of first initial strain increase component (xx) in the GLOBAL coordinate
system x-y-z.
- Value of second initial strain increase component (yy) in the GLOBAL coordinate system x-y-z.
- Value of third initial strain increase component (zz) in the GLOBAL coordinate system x-y-z.
- Value of fourth initial strain increase component (xy) in the GLOBAL coordinate system x-y-z.
- Value of fifth initial strain increase component (xz) in the GLOBAL coordinate system x-y-z.
- Value of sixth initial strain increase component (yz) in the GLOBAL coordinate system x-y-z.

Repeat this line if needed. The strain components should be given as Lagrange
strain components for nonlinear calculations and linearized strain components
for linear computations.

Examples:
*INITIAL STRAIN INCREASE
20,5,0.01,0.,0.01,0.,0.,0.

increases the initial strain at integration point 5 of element 20 by
a normal global x and normal global z component of 0.01, the other strains remain unchanged.

Example files: inistrain2.