** This test verifies displacement type damage evolution with exponential
** softening considering both energy and traction mode mix measures.
** The following have been incorporated in the test:
**	1. Uncoupled modes => *ELASTIC, TYPE=TRACTION
**	2. DAMAGE INITIATION CRITERION = MAXE
**	3. Deformation in each test case is considered either purely normal
**         (Mode 1) or purely in the shear (Mode 2) direction.
**	4. No temperature dependence
**	5. Isotropic shear behavior 
**	6. Thickness direction = Global 2 direction
**	7. Thickness = 1.0 => Nominal strain = Separation
*HEADING
  Damage test for COH2D4
*PREPRINT, MODEL=YES
**#####################################
**TEST CASE I: PURE TENSILE (MODE 1)
**TEST CASE II: SIMPLE SHEAR (MODE 2)
**#####################################
*NODE, NSET=SPEC1_MODE1
11, 0., 0.
12, 1., 0.
13, 1., 1.
14, 0., 1.
*SYSTEM
2, 0, 0
*NODE, NSET=SPEC1_MODE2
21, 0., 0.
22, 1., 0.
23, 1., 1.
24, 0., 1.
*NSET, NSET=SPEC1_MODE1_TOP
13, 14
*NSET, NSET=SPEC1_MODE1_BOT
11, 12
*NSET, NSET=SPEC1_MODE2_TOP
23, 24
*NSET, NSET=SPEC1_MODE2_BOT
21, 22
*ELEMENT, TYPE=COH2D4, ELSET=SPEC1_MODE1
11, 11, 12, 13, 14
*ELEMENT, TYPE=COH2D4, ELSET=SPEC1_MODE2
21, 21, 22, 23, 24
*ELSET, ELSET=EALL_DISP
SPEC1_MODE1, SPEC1_MODE2
**
*COHESIVE SECTION, RESPONSE=TRACTION SEPARATION, ELSET=EALL_DISP, MATERIAL=COH_DISP
*MATERIAL, NAME=COH_DISP
*ELASTIC,TYPE=TRACTION
4.0E6, 2.0E6, 2.0E6
*DAMAGE INITIATION, CRITERION=MAXE
0.002, 0.001
*DAMAGE EVOLUTION, TYPE=DISPLACEMENT, MODE MIX RATIO=TRACTION, MIXED MODE BEHAVIOR=TABULAR, SOFTENING=EXPONENTIAL
0.006, 2.0, 0.0
0.007, 2.0, 1.0
*DENSITY
100.
**
**#####################################
**TEST CASE III: PURE TENSILE (MODE 1)
**TEST CASE IV: SIMPLE SHEAR (MODE 2)
**#####################################
*SYSTEM
0, 2, 0
*NODE, NSET=SPEC2_MODE1
31, 0., 0.
32, 1., 0.
33, 1., 1.
34, 0., 1.
*SYSTEM
2, 2, 0
*NODE, NSET=SPEC2_MODE2
41, 0., 0.
42, 1., 0.
43, 1., 1.
44, 0., 1.
*NSET, NSET=SPEC2_MODE1_TOP
33, 34
*NSET, NSET=SPEC2_MODE1_BOT
31, 32
*NSET, NSET=SPEC2_MODE2_TOP
43, 44
*NSET, NSET=SPEC2_MODE2_BOT
41, 42
*ELEMENT, TYPE=COH2D4, ELSET=SPEC2_MODE1
31, 31, 32, 33, 34
*ELEMENT, TYPE=COH2D4, ELSET=SPEC2_MODE2
41, 41, 42, 43, 44
*ELSET, ELSET=EALL_ENER
SPEC2_MODE1, SPEC2_MODE2
**
*COHESIVE SECTION, RESPONSE=TRACTION SEPARATION, ELSET=EALL_ENER, MATERIAL=COH_ENER
*MATERIAL, NAME=COH_ENER
*ELASTIC,TYPE=TRACTION
4.0E6, 2.0E6, 2.0E6
*DAMAGE INITIATION, CRITERION=MAXE
0.002, 0.001
*DAMAGE EVOLUTION, TYPE=DISPLACEMENT, MODE MIX RATIO=ENERGY, MIXED MODE BEHAVIOR=TABULAR, SOFTENING=EXPONENTIAL
0.006, 2.0, 0.0
0.007, 2.0, 1.0
*DENSITY
100.
**
*NSET, NSET=NALL_BOT
SPEC1_MODE1_BOT, SPEC1_MODE2_BOT, SPEC2_MODE1_BOT, SPEC2_MODE2_BOT
*BOUNDARY
NALL_BOT, 1, 2
SPEC1_MODE1_TOP, 1, 1
SPEC1_MODE2_TOP, 2, 2
SPEC2_MODE1_TOP, 1, 1
SPEC2_MODE2_TOP, 2, 2
*ELSET, ELSET=QA_TEST_EALL
EALL_DISP, EALL_ENER
*NSET, NSET=QA_TEST_NALL_TOP
SPEC1_MODE1_TOP, SPEC1_MODE2_TOP, SPEC2_MODE1_TOP, SPEC2_MODE2_TOP
**#####################################
**DYNAMIC, EXPLICIT  STEP
**#####################################
*STEP
*DYNAMIC, EXPLICIT
, 1.0
*BOUNDARY, TYPE=VELOCITY
SPEC1_MODE1_TOP, 2, 2, 0.01
SPEC1_MODE2_TOP, 1, 1, 0.01
SPEC2_MODE1_TOP, 2, 2, 0.01
SPEC2_MODE2_TOP, 1, 1, 0.01
*OUTPUT, FIELD, NUMBER INTERVAL=20, TIME MARKS=YES
*ELEMENT OUTPUT, ELSET=QA_TEST_EALL
S, SDEG, LE, NE, DMICRT, STATUS
*NODE OUTPUT, NSET=QA_TEST_NALL_TOP
U, RF
*OUTPUT, HISTORY, TIME INTERVAL=0.01
*ELEMENT OUTPUT, ELSET=QA_TEST_EALL
S, SDEG, LE, NE, DMICRT, STATUS
*ENERGY OUTPUT, ELSET=SPEC1_MODE1
ALLSE, ALLKE, ALLDMD, ALLIE
*ENERGY OUTPUT, ELSET=SPEC1_MODE2
ALLSE, ALLKE, ALLDMD, ALLIE
*ENERGY OUTPUT, ELSET=SPEC2_MODE1
ALLSE, ALLKE, ALLDMD, ALLIE
*ENERGY OUTPUT, ELSET=SPEC2_MODE2
ALLSE, ALLKE, ALLDMD, ALLIE
*ENERGY OUTPUT
ETOTAL, ALLWK
*END STEP