Dear All,
I have written UMAT subroutine for GTN damage, to simulate Ductile crack growth with cleavage.
I am also calculating Weibull simultaenouly. However, as unfortunately I came to know that element deletion wont work with UMAT, but many researchers have reported using UMAT for failure simulation.
I have few question
1. If i degrade an element, will that element be out of calculation? i.e. will the crack grow?
I dont think so, but I may not know if it can happen!!
2. Therefore, I am using UDMGINI with UMAT along with enrichment of XFEM, but still I get error such as, PENALTY STIFFNESS to be augmented with Pressure overclosure or something, whats the way out? please help
3. Finally to make GTN damage nonlocal, I have to use common blocks for elements info, but I dont have any idea about common blocks, can somebody help me with some examples of common blocks especially used in context of element manipulation.
Thanks to all in advance.
With regards,
Abhishek
Dear Abhishek,
the use of UMAT together with UDMGINI requires that you define surface interaction properties for your enriched regions within the material block, because once an element is cracked, the crack surfaces can still be in contact in one of the following increments.
If you tried this approach here (https://www.researchgate.net/post/Can_I_use_XFEM_in_ABAQUS_613_with_my_own_plasticity_coupled_damage_initiation_and_evolution_criteria_developed_in_UMAT) and it didn't work, maybe you can post your input file.
Kind regards
Markus
Dear Markus Sir,
I used that approach and I am getting this error
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in keyword *SURFACEBEHAVIOR, file "Job-1_3.inp", line 5053: The keyword is misplaced. It can be suboption for the following keyword(s)/level(s): discreteinteractionproperty, surfaceinteraction, gap, interface
Analysis Input File Processor exited with an error.
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I have attached my input file with the subroutine file, please have a look and help me.
With regards,
Abhishek
now its giving this error
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The executable standard.exe aborted with system error code 1073741819. Please check the .dat, .msg, and .sta files for error messages if the files exist. If there are no error messages and you cannot resolve the problem, please run the command "abaqus job=support information=support" to report and save your system information. Use the same command to run Abaqus that you used when the problem occurred. Please contact your local Abaqus support office and send them the input file, the file support.log which you just created, the executable name, and the error code.
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Sir, its not .dll error as I have already done that, the input file responded to this error is attached.
I'm sorry, I'm using Linux on my work machine, so I don't know this error code
Please find attached input file. I am not able to get crack in the odb file please help me.
J'ai trouvé un problème de liaison entre UMAT et UDMGINI Pouvez-vous m'aider en écrivant un programme c'est-à-dire comment les organiser
Hello guys, thank you all for answering this question. However, I am wondering if we can use UMAT and UDMGINI at the same time. If yes, what would we write in the ABAQUS command line?
Should we write:
"ABAQUS job=example.inp user=UMAT.for & UDMGINI.for
????
Thank you for sharing your thoughts.
Regards,
Mehdi
If you want to implement both subroutines in one material, it is not possible. because damage initiation should be implemented in UMAT. However, if you want to use it in different materials, you can put both subroutines in one Fortran file and other points.
Find more details in the following link:
https://caeassistant.com/questions/question/using-multiple-subroutines
Dear Abhishek,
I also encountered this problem, did you solve this problem, can you tell me the solution?
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