Problems about the Contact Roller of the 3D FE Model in ADINA

Dear everyone,

Recently I am running a 3D FE model in ADINA to
analyse the elastic-plastic fracture behaviour.

A three-point bending specimen was modeled and the specimen was
supported by a contact roller.

Here is the problem:

In a rather small loading (load line displacement was about 0.1mm),
the program indicated that “the mesh is
too distorted” and stopped running. It also showed “No convergence” and stopped if the small strain formulation was
used.

The 2D model with the same mesh has no such problems. Also, I
directly applied constraint on the specimen instead of using the support contact
roller and no errors appeared in the running. Hence, the problem must be in the
support contact roller.

Following is the command of the contact roller:

CGROUP CONTACT3 NAME=2 FORCES=YES TRACTION=YES NODETONO=NO,

    
FRICTION=0.500000000000000 EPSN=1.00000000000000E-12,

     EPST=0.00100000000000000
DIRECTIO=NORMAL CONTINUO=YES,

     INITIAL-=ALLOWED
PENETRAT=ONE DEPTH=0.00000000000000,

     OFFSET=0.00000000000000
OFFSET-T=CONSTANT CORNER-C=NO,

     TBIRTH=0.00000000000000
TDEATH=0.00000000000000 TIED=NO,

     TIED-OFF=0.00000000000000
HHATTMC=0.00000000000000,

     FCTMC=0.500000000000000
FTTMC=0.500000000000000 RIGID-TA=YES,

    
NORMAL-S=1.00000000000000E+11 TANGENTI=0.00000000000000,

    
PTOLERAN=1.00000000000000E-08 RESIDUAL=0.00100000000000000,

     LIMIT-FO=1.00000000000000
ITERATIO=2 TIME-PEN=0.00000000000000,

     CONSISTE=DEFAULT
USER-FRI=NO DESCRIPT='NONE',

     CFACTOR1=0.00000000000000
CS-EXTEN=0.00100000000000000,

     ALGORITH=DEFAULT
RTP-CHEC=NO RTP-MAX=0.00100000000000000,

     XDAMP=NO
XNDAMP=0.100000000000000 SLIDING-=1.00000000000000E-10,

     TENSILE-=0.00100000000000000 OSCILLAT=5,

     GAP-BIAS=0.00000000000000
OFFSET-D=AUTOMATIC DISPLACE=DEFAULT,

     FRIC-DEL=NO
GAP-VALU=0.00000000000000 TENS-CON=YES FREE-OVE=NO,

     GAP-PUSH=0.00000000000000
EKTMC=0.00000000000000

*

CONTACTSURFA NAME=1 PRINT=DEFAULT SAVE=DEFAULT SOLID=NO BODY=0,

     ORIENTAT=AUTOMATIC
MARQUEEB=0 DESCRIPT='NONE'

@CLEAR

973 1 0

962 1 0

@

*

CSURFACE NAME=1 NODES=4 PATTERN=1 NCOINCID=SURFACE,

    
NCTOLERA=1.00000000000000E-05 SUBSTRUC=0 GROUP=2

*

CONTACTSURFA NAME=2 PRINT=DEFAULT SAVE=DEFAULT SOLID=NO BODY=0,

     ORIENTAT=INPUT SENSE=1
MARQUEEB=0 DESCRIPT='NONE'

@CLEAR

9 -1 0

@

*

CSURFACE NAME=2 NODES=4 PATTERN=1 NCOINCID=SURFACE,

    
NCTOLERA=1.00000000000000E-05 SUBSTRUC=0 GROUP=2

*

CONTACTPAIR NAME=1 TARGET=2 CONTACTO=1 FRICTION=0.500000000000000,

     TBIRTH=0.00000000000000
TDEATH=0.00000000000000,

     HHATTMC=0.00000000000000
FCTMC=0.00000000000000,

     FTTMC=0.00000000000000
NX=0 NY=0 NZ=0 OFFSETCO=BOTH,

     EKTMC=0.00000000000000

I am wondering if anyone can kindly give me some suggestions
on this problem.

Thank you and have a good day!

Yifan Huang