Hi everyone,
I am trying to model composite failure in abaqus. I used USDFLD to check different failure mode (fiber tension/compression, matrix tension/compression,..) based on available theory of failure. After checking the failure, if any element fails, the material property like stiffness will suddenly reduces to near zero. At this time i need to chnage material stiffness in UMAT and getting new stress distribution.
My problem is in the input file (inp file) how can I use both command for USDFLD and UMAT?
Here is a part of my input file:
*MATERIAL,NAME=T300
*ELASTIC,TYPE=LAMINA,DEPENDENCIES=5
22.7E6,1.88E6,0.23,1.01E6,1.01E6,1.01E6,0.,0,0,0,0,0
1E0,1.00E0,0.00,1E0,1E0,1E0,0.,1,1,0,0,0
22.7E6,1.E0,0.0,1.01E6,1.01E6,1.01E6,0.,0,0,1,1,0
22.7E6,1.88E6,0.00,1E0,1E0,1E0,0.,0,0,0,0,1
22.7E6,1.00E0,0.00,1.00E0,1.01E6,1.01E6,0.,1,1,1,1,1
*DEPVAR
5,
*USER DEFINED FIELD
*MATERIAL,NAME=T300
*USER MATERIAL,CONST=6,TYPE=MECHANICAL
22.7E6,1.88E6,0.23,1.01E6,1.01E6,1.01E6
** LOCAL ORIENTATION: 90 DEG. CW. WRT GLOBAL SYSTEM
*ORIENTATION,NAME=LOCAL
0.,1.,0.,-1.,0.,0.
3,
*SHELL SECTION,COMPOSITE,ELSET=PLATE,ORIENTATION=LOCAL
0.06750,1,T300,45
0.06750,1,T300,-45
I am wondering if somebody help to to see why the above code has problem, and how to write both user material and user defined field in the same inp file.
Regards,
Mehdi
UMAT &USDFLD
Hi,
Your input file seems to be fine. There are no parameters associated in conjunction with USDFLD. JUSt make sure that you keep your USDFLD routine in umat.for and call for umat using (abaqus job=job.inp user=umat.for interactive)
Thanks and Regards,
U.N.S. ROHITH
strain rate dependent for cohesive element
Hi everyone,
I am trying to model cohesive element that incorporate the strain rate-dependent parameters in the ABAQUS. As we know, Abaqus can implement temperature-dependent behavior in the model. So, does anyone know how to input the strain rate-dependent behavior in the ABAQUS?I have been facing this problem almost 2 weeks.
Thank you.
USDFLD
Hello
study the example on USDFLD in the subroutine manual. You need to adapt it to get the increment in strain , and then divide by the time incrment to arrive at the strain rate.
Good luck
Frank
------------------------------------------
Ruhr-University
Bochum
Germany
umat & usdfld
hi mr naderi
I want to combine umat and usdfld, can I help me?
in section of property material in abaqus should be to determine depvar,userdefined field and user material?
or determine user material enough?
tnx for help
Regards,
Mehdi taheri