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Dear All,

I am using Huang subroutine for my model which is a polycrystal of FCC material. The problem is that I faced with the error code 145 in Abaqus which is related to singularity. Does anyone have any idea that what I should do?

Thank you,

Arman,

hi ,

How to vary strain rate in abaqus explicit in tensile test simulation.

i know the expression in tensile test that strain rate = velocity / gauge length, but how can m decide the step time.

for example if the strain rate is 100 sec-1, and gauge length is 25 mm thn the velocity is 1.66*e-5 m/s. so what is the step time in this case................

any body tell me the relation between strain rate and step time.

thanks in advance

Dear All,

I have a model with the length of 1000 mm and I want to apply tensile displacement up to strain=0.035 at the strain rate of 1e-6 1/s. I considered the time step as 1 and put 35 in x direction to have the strain of 0.035 but I don't know how I can have this strain rate that is mentioned above by changing amplitude section in B.C? 

I am wondering if you can help me by answering this question.

Thank you,

Arman 

Hi all,

I mistakenly poste this in the blog and i am now reposting it where it should have been. 

I have a  20 node hexahedral "Thermomechanical" element in our inhouse software which i am trying to validate against Abaqus .

The problem is, the displacements, nodal forces match exactly ( Just compared the max min values in the legends! and checked a few random nodes).

The Abaqus input file is attached:

The problem is as follows:

Dear all users

I am working with a conical shell which is partitioned in its higth for assigning different sections. How would it be possible for me to connect these separations to have a structure. I mean i want to connect them just from a section which is belong to tow different parts and i upload its image.

regards.

_Hi 

Could you please tell me how to create a *Beam General Section(abaqus) for triangular element with all sieds are equal.

Ravi 

Greetings,

I was recently writing an ambitious code for a certain mechanical system when I had a bright idea. Basically I have two materials that adhere together. What I would ideally like to do is deactivate the second material after the strain in the first material reaches a certain limit. So the pseudo code would look like:

If [Strain in material 1 <= Limit]

Young's Modulus of Material 2 == 0 (Or very close to zero)

end

hi

Please I need your help :(

I would like to apply a periodic boundary condition on a composite material.

I am using abaqus.

I want to apply a shear strain e12 of 0.001.

Hpw would I implement the strain to a reference node?

Can i put the rotation around axis 3 to be 0.001?

Is it the same?

Thank you

HI,

While I tried to simulate a simple uniaxial loading and a simple cube geometry ( single crystal)- I obtaine d zero reaction forces at the constraint nodes.. while in Animation the displacements are fine. I could see the stretching of the specimen but i am getting absolute zero values of stresses and reaction forces.

I have used UMAT many time and I am facing this particular problem in recent times. Is there anything to do with the .inp file ?

If any of you have encountered a similar problem, kindly help !!

-Prithivi