Hi All,

 I would like to use Abaqus to model the viscoelastic material  behaviour of a polymer.

I have material data from a simple uniaxial creep experiment (nominal strain vs time).  I tried to use the viscoelastic material model in Abaqus.  I am a bit confused as to how I need to enter my data (what format). 

The manual says I have to specify the normalized bulk and normalized shear compliance . 

Hi

I’m trying to develop a VUMat routine so I’ve already
started to learn its features. I recently got this problem that what exactly
the variable stepTime means! I created a model with 3 steps including the initial
step and I coded my routine somehow that when the stepTime is equal to 0 it
prints something into a file. Surprisingly only once in whole analysis the
stepTime would be 0 and that’s exactly at the beginning of the analysis when
totalTime is in fact 0. Could anyone please explain why this happens?

Thanks

Dear Abaqus Users,First of all, I want to clarify that I am a beginner in Abaqus (only few months) and new in iMechanica. I have been modeling an excavation in Abaqus/CAE. I am using several layers of soils which have been modeled using Mohr-Coulomb model, the wall as an elastic material.

Hello,

I am a new user of Abaqus and need to model a glued connection between 2 solid elements (the nodes on both elements must have same displacement, no relative movement between them). In other software (cosmos/m for instance) this is accomplished by merging these overlapping nodes.

I need to do this in Abaqus, looked in the huge Abaqus documentation, but it is hard to find this for complete beginner. Please help.   

I encounter a big challenge now.

I wanna use mohr-coulomb criterion to simulate the indentation of BMGs in ABAQUS.However, there are many parameters confusing me.

We know the  mohr-coulomb can be written as:

                            τc=k0-ασn

Hi,

Does any body know if MATLAB functions and scripts can be called into an ABAQUS subroutine like UMAT?

Alankar

Graduate Student, Washington State University, Pullman, WA

Hi
I have script written in phyton and get following error when try to read history data.
I will appreciate any help.
thanks and regards,

ERROR:

Neither set named 'PIVOT' nor region named 'ElementSet PIVOT' found.

***COMMENT: History output is available at the following points ['Element PART-1-1.701', 'Element PART-1-1.908', 'Element PART-1-1.909', 'Node PART-1-1.901', 'Node PART-1-1.902', 'Node PART-1-1.903', 'Node PART-1-1.904']

***ERROR: The spatial location for the requested history not found in the historyRegion objects of step 'Step-1'.

***ERROR: No history data in output database

Help! imechanica!

This might not be a smart question to ask, but if any of you can help me, it'd be great.

 I have a DCB (sandwitch specimen) with a cohesive element in the middle. Studying pure Mode I case, displacement is applied at the end of the DCB. Cohesive element works great (it fails when one reaches max separations).  But I am having a difficulity in extracting crack length (i.e. length of failed cohesive element) vs time step. I looked for Damage and Status commend, but it's not promising.  (I'm pretty new to ABAQUS....)

 If you have worked on cohesive elements, and know where those (filed maybe?) output of failed element lengths can be found, could you please help?

 Thanks~ masa

Hi All,

I am analysing a fiber composite solid plate with a large and small holes. The model is meshed with C3D8R elements. The output has U and RF in global CSYS and S, E in local CSYS. I have problem in reading  S and E written in local CSYS. I know it is very simple, but I cant able to figure it out. Those who know, how to read the S and E in local CSYS, please help me. Tks in advance for your time and advice.

Regrads

Jacob 

Hello everyone:

1.  I have built a FEM model 2D plane strain using ABAQUS/Standard (CPE4R) elements,

2. I am  modeling the contact between a cylinder and a plate in 2D.

3. The Cylinder material is given is ELASTIC ISOTROPIC material with no plasticit E=310 GPa

4.  The plate is with a Ramberg-Osgood plasticity with a Young's modulus E=210 GPa.

5. The mesh at the the contact point is VERY refined element characteristic length is about 1 micron. (My model units are  (mm,N,sec)).

6. I validate my model with hertz contact theory and it works well.

Hi all,

I'm trying to model a peel T test on a composite material composed of steel and polymer (polypropylen) on Abaqus 6.7. Between these parts, there are cohesive elements COH3D8.
I have a problem with my model and I don't understand it. You can visualize my results in attachs files.
For understand this draw, a few precisions:
The elements in white has just here to guide the materials.
In B (cf attachs files), the nodes are embedded.
In A I applied a velocity.
In C I applied rotation constraints and coupling constraints on all rotations and displacements.
My structure present a strange evolution in the red circle. I don't understand this.

These days I've been applying oneself to implement the Chaboche viscoplastic model in ABAQUS user-subroutine for simulating the cyclic loading in single crystals.
The procedure can easily get out. I'm not sure about the problem, the deduction of Jacobian, the convergence? 
Btw, I know there is free subroutine for crystal plasticity by Huang YG. I wonder if the UMAT routine for chaboche model is available, then I can generalize it to fit for my case.
If pity there isn't, guide or example for viscoplastic model can be of great help also.
Thanks a lot

maxianfeng@gmail.com

I am trying to create a model of a travelling wave ultrasonic motor and have found it difficult to find out how to apply the natural frequency of a steel ring to it at two seperate points, seperated by an angle of about 11 degrees. Any ideas or help would be appreciated.

I am trying to create a model of a travelling wave ultrasonic motor and have found it difficult to find out how to apply the natural frequency of a steel ring to it at two seperate points, seperated by an angle of about 11 degrees. Any ideas or help would be appreciated.

Dear, I use the abaqus present , how can apply a tightening torque between an implant (screw) and the bone with abaqus......... thank you ¶

Please, I need some EFD or CFD software that has an Student Version. I have to make an analysis Solid-Fluid and vice versa, but i have no software to make that.

Now I'm using Pro/E to make Streches and statics analysis, but i cant do any EFD or CFD without any patch or software.  Anyone knows any?

Tanks! 

I have noticed that a lot of people are using UMAT and VUMAT material model
subroutines for their researches. However, most of these subroutines do not
find their way to free code market and remain in the hands of the developers.
Therefore, a lot of wheel re-inventing has to be done by other people. Since
development and testing of a material subroutine takes a damn long time, I
think it is a good idea if each of us can share the subroutines she has
developed with the others. I know that a couple of subroutines are publicly
available and many other people also know that. Please comment about less-known
freely available subroutines.

I have noticed that a lot of people are using UMAT and VUMAT material model
subroutines for their researches. However, most of these subroutines do not
find their way to free code market and remain in the hands of the developers.
Therefore, a lot of wheel re-inventing has to be done by other people. Since
development and testing of a material subroutine takes a damn long time, I
think it is a good idea if each of us can share the subroutines she has
developed with the others. I know that a couple of subroutines are publicly
available and many other people also know that. Please comment about less-known
freely available subroutines.

Hi,

I started modelling the
behaviour of the reinforced concrete walls under cyclic loading using
ABAQUS/Explicit.  I used a shell element part with solid homogeneous
section and defined the concrete behaviour using concrete damaged plasticity
material definition. Embedded truss elements were used to define the steel
rebars. In 2 different steps (left and right) I defined the cyclic loading (in
plane) as imposed displacement (using amplitude-smooth step).

My question are:

1. Is it correct to define
the cyclic loading in this meaner? 

I am trying to built a model for a laminated angle-plied plate, which has different fibres orientation in each plate. But I have a problem in materilas property as the Abaqus told me after analysis andmake error. The error is that the properties of the model in not assigned well. I have assign them as shell composite and make the local co-ordinate orientation.

I have tried to use homogeneous material and enter the Engineering contants in all directions and by just changing the local axis orintation, it works. But I don't know if this is right or not.

Need advice plz

Hi everyone

can anyone tell me how to use "display group" option in ABAQUS.

i have to find the total reaction force of set of all nodes on a particular surface. i had tried many times using "display group" option. but couldnt succeded.

or is there any other option to get the data from those set of nodes on a surface.  we have this kind of option in ANSYS, but what will the corresponding feature in ABAQUS.

Please help me in this regard. 

cheers

Ravitej 

This computer assignment is due Friday, Nov. 16, 2007

Please download and read the following materials.
 

1-1 ABAQUS tutorial for ES 240.pdf

1-2 Learning ABAQUS.pdf    

1-3 CAE Example.pdf

ABAQUS is a suite of powerful general purpose engineering simulation programs based on the finite element method.

1.1 Features

Abaqus contains an extensive library of elements that can model virtually any geometry.