*HEADING
   2D Double cantilever beam test model 
   - use vcct *debond to model crack growth
   - use cohesive elements to predict the onset of debonding
   E=8msi, v=0.3, Gic=0.8, B=1.0, t=0.4    
**PREPRINT,MODEL=YES
*NODE
    1,  0.0, 0.0, 0.0
    5,  0.0, 0.2, 0.0
    6,  0.0, 0.2, 0.0
   10,  0.0, 0.4, 0.0 
**  
**
 4001,  4.03, 0.0, 0.0
 4005,  4.03, 0.2, 0.0
 4006,  4.03, 0.2, 0.0
 4010,  4.03, 0.4, 0.0  
**
 8001,  8.03, 0.0, 0.0
 8005,  8.03, 0.2, 0.0
 8006,  8.03, 0.2, 0.0
 8010,  8.03, 0.4, 0.0  
**
 9001,  9.0, 0.0, 0.0
 9005,  9.0, 0.2, 0.0
 9006,  9.0, 0.2, 0.0
 9010,  9.0, 0.4, 0.0  
**
*NGEN,NSET=L1
    1,   5,1
    6,  10,1
*NGEN,NSET=L2
 4001,4005,1
 4006,4010,1
*NGEN,NSET=L5
 8001,8005,1
 8006,8010,1
*NGEN,NSET=L6
 9001,9005,1
 9006,9010,1
**
*NFILL,NSET=ALLN
L1,L2,40,100
*NFILL,NSET=ALLN
L2,L5,40,100
*NFILL,NSET=ALLN
L5,L6,10,100
**
*NSET,NSET=BC,GENERATE
9001, 9004
9006, 9010
*nset,nset=nboun
7
*BOUNDARY
BC,1,3
**
**
*ELEMENT,TYPE=CPE4
1, 1, 101,102, 2
6, 6, 106,107, 7
**
*ELGEN,ELSET=EBASE
1, 90,100,100, 4, 1,1
6, 90,100,100, 4, 1,1
*ELSET,ELSET=BOT,gen
 4, 8904, 100
*ELSET,ELSET=TOP,gen
 6, 8906, 100
** 
**
*SOLID SECTION,ELSET=EBASE,MATERIAL=BMAT
**
*MATERIAL,NAME=BMAT
*ELASTIC, TYPE=ISO
      8.0E+6,         0.3
**
**
*NSET,NSET=BNODES,GEN
 105, 9005, 100
*SURFACE,NAME=BOT
 BOT, S3
*SURFACE,NAME=TOP
 TOP, S1 
*NSET,NSET=AD,GEN
 5,9005,100
*CONTACT PAIR, INTERACTION=FRACT,ADJUST=BNODES
 BOT, TOP
*SURFACE INTERACTION, NAME=FRACT
1.0
**SURFACE BEHA,AUG
**
*INITIAL CONDITIONS,TYPE =CONTACT
 BOT, TOP, BNODES
**
*element, type=coh2d4, elset=coh
999999, 5, 105, 106, 6
*cohesive section, elset=coh, material=mat1, response=traction separation, thickness=specified, controls=cont
1.0, 1.0
*material, name=mat1
*elastic, type=traction
8.0e5, 8.0e5, 8.0e5
*damage initiation, criterion=maxe
0.9e-6, 0.9e-6
*damage evolution, type=energy, mixed mode behavior=bk, power=1.75
0.8, 0.8
*section controls, name=cont, element deletion=yes, max degradation=0.95
*STEP,NLGEOM, INC=5000
*STATIC
0.005, 1,, 0.1
*CONTROLS,PARAMETERS=TIME INCREMENTATION
 , , , , , , 50
**CONTACT PRINT
*DEBOND,SLAVE=BOT,MASTER=TOP,FREQ=1
*FRACTURE CRITERION,TYPE=VCCT
0.8, 0.8, 0.0, 1.75
*BOUNDARY
  4, 2,2, -0.16
  7, 2,2, 0.16
**print,contact=yes
*output,field,freq=10
*element output
s
**s, e, dmicrt
*element output, elset=coh
sdeg, status
*node output
u
**u, rf
*contact output,SLAVE=BOT,MASTER=TOP
dbt,dbsf,dbs,openbc,crsts,enrrt,efenrrtr,bdstat
*output, history
*node output,nset=nboun
u2
rf2
*END STEP