zone geometry-tolerance command

Syntax

zone geometry-tolerance f

Set the tolerance before an illegal geometry error happens in response to zone deformation. The user input f is the minimum ratio of the volume of a tetrahedral subzone to the zone volume. FLAC signals an illegal geometry error if that ratio is less than f for any tetrahedral (3D) or triangular (2D) subzone in the model. The default value is 0.0.

Note: Be aware that zone geometry is checked only every 10 steps in large-strain mode. So, if the tolerance is set too close to zero, an error may be signaled elsewhere in the calculation before exiting at the selected ratio. Also note that the typical minimum ratio of the subzone volumes to the full zone volume are 0.2 in FLAC3D and 0.5 in FLAC2D. So the maximum value selected for the ratio should be less than these values to avoid premature termination of cycling.