!ELEMENT_ACTIVATION

Definition of element activation/deactivation

Parameter

MODE      = Control mode (FIXED, AMPLITUDE, DAMAGE) [required]
STATE     = State of elements (ON: active, OFF: inactive) (required for MODE=FIXED)
AMP       = Amplitude name (required for MODE=AMPLITUDE)
MEASURE   = Quantity to check (STRESS, STRAIN) (required for MODE=DAMAGE)
EPSILON   = Coefficient for dummy stiffness (default: 1.0E-6)
GRPID     = Control group ID

** 2nd line or later **

When MODE = FIXED, AMPLITUDE

ELEM_GRP_NAME

When MODE = DAMAGE

ELEM_GRP_NAME, LOWER, UPPER

Parameters	Attributions	Contents
ELEM_GRP_NAME	C	Element group name
LOWER	R	Lower bound of stress/strain value
UPPER	R	Upper bound of stress/strain value

Example of Use

!ELEMENT_ACTIVATION, MODE=FIXED, STATE=OFF, EPSILON=1.0E-3, GRPID=1
PART_1
!ELEMENT_ACTIVATION, MODE=AMPLITUDE, AMP=AMP1, EPSILON=1.0E-3, GRPID=2
PART_2
!ELEMENT_ACTIVATION, MODE=DAMAGE, MEASURE=STRESS, EPSILON=1.0E-6, GRPID=3
PART_3, 100.0, 200.0
!STEP, SUBSTEPS=10
BOUNDARY,1
LOAD,1
!STEP, SUBSTEPS=10
BOUNDARY,1
LOAD,1
ELEMACT,1
!STEP, SUBSTEPS=10
BOUNDARY,1
LOAD,1
ELEMACT,1
ELEMACT,2

Remarks

• Use MODE to select the behavior exclusively (MODE=FIXED|AMPLITUDE|DAMAGE).
• With MODE=FIXED, elements are always active/inactive according to STATE=ON/OFF.
• With MODE=AMPLITUDE, elements are switched by amplitude value (amp_val > 0.5 => active, otherwise inactive).
• With MODE=DAMAGE, elements are deactivated when the selected MEASURE=STRESS|STRAIN goes out of range (not satisfying LOWER ≤ value ≤ UPPER). Once deactivated, they are not reactivated.
• Control groups specified by GRPID are activated by ELEMACT, id within !STEP.
• If ELEMACT, id is not specified in !STEP, the corresponding element activation setting is not applied.