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Hello everyone.

I am trying to do something with the deformation gradient in UMAT. I used F=DFGRD0 as the gradient. but i found that it always comes to be a identity tensor not only for the case of a 3d isotropic elastic material but also for the ramberg osgood model. it was very surprising for me so i also tried to print DFGRD1 it was also identity tensor.

I have used a C3D8 single element and was doing the uniaxial test. Please help me out with this

Hello friends,
Here is the Abaqus user subroutine for Functionally Graded Material with direct integration method. This Umat is based on S.H.Song's Umat. Obviously the coefficient AAA in calculating E is the ratio of young moduli of  two sides of the plate. With this method, one can change young modulus through the thickness.

But I have problem with changing density through the thickness, meaning from density of ceramic to density of metal.
I would be grateful if anyone can help me. Any help would be appreciated.

Hi all, 

I'm trying to create a full-scale truss for a static loading simulation using Abaqus.
I wanted to use a Python script to do this, but I am not very experienced with this language or the Abaqus methods.

The members forming the truss are cee sections. However, at the ends of the cee sections I want to create an extruded cut

like so:
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However, when I try to use the CutExtrude command, Abaqus keeps giving me an "Invalid sketch plane" error even though I'm sure that the face I'm putting in the CutExtrude method is correct.

Hi all:

I am a master student and got a question about abaqus.

I have a model and want to open it. But when i type abaqus user = ***.f, it shows later that I need to input the 'identifier' and 'input file'. how can I solve this and what should I type in these parts?

BTW, there are many .inp files and I have no idea which one to choose.

Sincerely hoping for response.

Thanks a lot

Hi guys, I’m trying to apply on ABAQUS to do my MSc thesis, which is about a non linear buckling analysis of concrete filled tubes. In other words, I have to model on abaqus some compression tests of tubes filled with concrete, including initial deformations, contact properties and at the end load eccentricities. I read that to perform a quasi static analysis with nonlinearities the best way is the Dynamic Explicit Analysis, so I’m reading about that but unfortunately I have some doubts.

Hi everyone,

I'm a PhD student in the first year. My PhD subject is to numerically study the low cycle fatigue (LCF) using the Abaqus software. Currently, I met a error in my simulation as below:

I know it's common thing but how do i go about fixing this

Abaqus Error: 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.

What are the steps? 

I am trying to define the remeshing rule on my dynamic explicit model but when I click the remeshing toogle, It gives me 'no error variables are valid for the selected step ' error message. If someone can help me about solution of this problem, I will be appreciated.

We ran the steady state dynamic. Modal case with requested field output of TA & A,

please explain TA & A in detail, here i want to understand definition & difference between TA & A, in which case i request TA and in which case i request A, can you please explain with simpler example case

i am beginer in this dynamic analysis case,