*HEADING
*PREPRINT,MODEL=YES,HISTORY=NO
**
** TEST 1: SPRING/CONNECTOR
**
*NODE,NSET=NALL
1,  0.0, 1.
2,  1.0, 1.
11, 0.0, 0.
12, 1.5, 0.
*NSET,NSET=LEFT
1,11
*NSET,NSET=MID
12, 
*ELEMENT,TYPE=SPRINGA,ELSET=SPRINGA
1, 1,2
*SPRING,ELSET=SPRINGA

10
*ELEMENT,TYPE=CONN3D2,ELSET=CONN
11,11,12
*CONNECTOR SECTION,ELSET=CONN,BEHAV=beh
axial
*CONNECTOR BEHAVIOR,NAME=beh
*CONNECTOR ELAS,COMP=1
10
*connector friction,comp=1
1.0
*friction
0.0
*ELSET,ELSET=TEST
11,
*AMPLITUDE,NAME=RAMP
0.,0., .5,1.0
**
**
*STEP,NLGEOM
 STEP #1: DISPLACE TEST SPECIMEN SO FINAL SHAPE IS
          IDENTICAL TO INITIAL SHAPE OF REFERENCE ELEMENT 
*STATIC
0.25,1.
*PRINT,MODEL CHANGE=YES
*BOUNDARY,AMP=RAMP
NALL,3
LEFT,1,6
MID,1,1,-0.5
MID,2,2
*NODE PRINT,FREQ=999
RF, 
COORD,
*OUTPUT,HISTORY,FREQUENCY=1
*ELEMENT OUTPUT,ELSET=SPRINGA
S,E
*ELEMENT OUTPUT,ELSET=CONN
CU,CEF
*OUTPUT,FIELD,FREQUENCY=1
*NODE OUTPUT
 U
*ELEMENT OUTPUT,ELSET=CONN
 CU,CEF
*END STEP
**
**
*STEP,NLGEOM
 STEP #2: REMOVE TEST ELEMENTS
*STATIC
1.,1.
*MODEL CHANGE,REMOVE,TYPE=ELEMENT
TEST,
*NODE PRINT,FREQ=999
RF, 
COORD,
*OUTPUT,HISTORY,FREQUENCY=1
*ELEMENT OUTPUT,ELSET=SPRINGA
S,E
*ELEMENT OUTPUT,ELSET=CONN
*OUTPUT,FIELD,FREQUENCY=1
*NODE OUTPUT
 U
*END STEP
**
**
*STEP,NLGEOM
 STEP #3: ADD TEST ELEMENTS BACK IN STRAIN-FREE
*STATIC
1.,1.
*MODEL CHANGE,ADD=STRAINFREE,TYPE=ELEMENT
TEST,
*BOUNDARY,OP=NEW
LEFT,1,6
*NODE PRINT,FREQ=999
RF, 
COORD,
*OUTPUT,HISTORY,FREQUENCY=1
*ELEMENT OUTPUT,ELSET=SPRINGA
S,E
*ELEMENT OUTPUT,ELSET=CONN
CU,CEF
*OUTPUT,FIELD,FREQUENCY=1
*NODE OUTPUT
 U
*ELEMENT OUTPUT,ELSET=CONN
 CU,CEF
*END STEP
**
**
*STEP,NLGEOM
 STEP #4: APPLY LOAD TO BOTH ELEMENTS 
*STATIC
0.25,1.
*BOUNDARY,AMP=RAMP,TYPE=VELOCITY
2,1,1,.3
2,2,2,.3
12,1,1,.3
12,2,2,.3
*END STEP
**
**
*STEP,NLGEOM
 STEP #5: REMOVE TEST ELEMENT
*STATIC
.25,1.0
*BOUNDARY,OP=NEW,FIXED
NALL,1,3
*MODEL CHANGE,REMOVE,TYPE=ELEMENT
TEST,
*NODE PRINT,FREQ=999
RF, 
COORD,
*OUTPUT,HISTORY,FREQUENCY=1
*ELEMENT OUTPUT,ELSET=SPRINGA
S,E
*OUTPUT,FIELD,FREQUENCY=1
*NODE OUTPUT
 U
*END STEP
**
**
*STEP,NLGEOM
 STEP #6: ADD TEST ELEMENTS BACK IN WITH-STRAIN
*STATIC
.25,1.0
*MODEL CHANGE,ADD=WITHSTRAIN,TYPE=ELEMENT
TEST,
*NODE PRINT,FREQ=999
RF, 
COORD,
*OUTPUT,HISTORY,FREQUENCY=1
*ELEMENT OUTPUT,ELSET=SPRINGA
S,E
*ELEMENT OUTPUT,ELSET=CONN
CU,CEF
*OUTPUT,FIELD,FREQUENCY=1
*NODE OUTPUT
 U
*ELEMENT OUTPUT,ELSET=CONN
 CU,CEF
*END STEP
**