zone initialize command


zone initialize keyword <range>

Primary keywords:

density    extra    fluid-density    state    stress    stress-principal    stress-xx    stress-xy    stress-xz    stress-yy    stress-yz    stress-zz

Initialize a variable on all zones in the range.

Note that among the keywords, there is similarity between the stress xx construction of the command and the stress-xx construction. The difference is that the former will allow multiple components to be specified at once (e.g., zone initialize stress xx 1 yy 2.4 zz 4.7) but cannot take a value modifier (that is, vary, multiply, etc.). Also be aware that when this command form is used, the entire stress tensor is initialized — any components not specified explicitly are assumed to be zero. The latter construction allows modifiers (e.g., zone.initialize.stress-yy 2.2 add 3) but each component must be separately specified.

Note that in FLAC3D, compressive stresses are negative.

The available keywords are:

density f [zoneinitializeblock]

mass density of zone

extra i a[zoneinitializeblock]

extra variable for array index i

fluid-density f [zoneinitializeblock]

fluid mass density in zone (only available if model configure fluid has been specified)

state i [zoneinitializeblock]

The plasticity indicators for tetrahedrons are set to i . Normally the value of i used is 0 in order to reset the failure indicators.

stress <keyword ...>

Full stress state, specified by component. A component that is not specified is assumed to be zero.

xx f

xx-component of stress

xy f

xy-component of stress

xz f

xz-component of stress

yy f

yy-component of stress

yz f

yz-component of stress

zz f

zz-component of stress

stress-principal <keyword ...>

Principal stress states, specified by value and by direction using the available keywords. Note that at least two directions must be specified, and magnitudes not specified are assumed to be zero. Note that the [zoneinitializeblock] is available after each of the following keywords, allowing them to be varied in space independently.

direction-intermediate v [zoneinitializeblock]

Direction of intermediate principal stress.

direction-maximum v [zoneinitializeblock]

Direction of maximum principal stress.

direction-minimum v [zoneinitializeblock]

Direction of minimum principal stress.

intermediate f [zoneinitializeblock]

Intermediate principal stress magnitude.

maximum f [zoneinitializeblock]

Maximum (most postitive) principal stress.

minimum f [zoneinitializeblock]

Minimum (most negative) principal stress.

stress-xx f [zoneinitializeblock]

xx-component of stress (See the description above for the difference between zone initialize stress-xx and zone initialize stress xx and for the next five keywords).

stress-xy f [zoneinitializeblock]

xy-component of stress

stress-xz f [zoneinitializeblock]

xz-component of stress

stress-yy f [zoneinitializeblock]

yy-component of stress

stress-yz f [zoneinitializeblock]

yz-component of stress

stress-zz f [zoneinitializeblock]

zz-component of stress

zone initialize Keyword Block

The following keywords may be used to modify a supplied value. If the description of the modifier keyword mentions what type of value it may be applied to (e.g. scalar value, vector value, etc.), be sure there is a match between the modifier and the main keyword value. The commands main keywords are: density, extra, fluid-density, state, stress-xx, stress-xy, stress-xz, stress-yy, stress-yz and stress-zz. direction-intermediate, direction-maximum, direction-minimum, intermediate, maximum and minimum.


Add the specified value to the existing value.

gradient v <origin v >

Apply a gradient to the scalar-value provided.


Multiply the existing value by the specified value.

vary v

Apply a linear variation to the scalar-value provided.