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Hi,

I have an easy question. 

I want to run a "dcb_vcct_fatigue_2d.inp" example. I tried abaqus fetch job= dcb_vcct_fatigue_2d.inp but an error ocurred. 

I have difficulty accepting the definition of "nominal strength" and "net strength" given in Shigley's Mechanical Engineering Design.

Consider a plate of width w, thickness t, with a hole of diameter d centered at w/2, loaded with force F.  

Shigley's says: the "net stress" is \sigma_net=F/(wt) and the "nominal stress" is \sigma_nominal=F/((w-d)t). ==> I think he is wrong!

According to: http://dictionary.reference.com/

Net:

— noun

Hi everyone,

I am recently implementing gradient crystal plasticity using FEM. As I understand, in order to obtain gradient of some plastic parameters (e.g. gradient of slip), additional dof (e.g. slip) should be added to each node and be interpolated with shape funcitons. And unlike conventional plasticity, which slip increment is computed locally at every integration point with stress update algorithm, both diaplacement increment and slip increment is computed globally.

Greetings,

Im running a model with using the vumat subroutine and the elastic part compatible with the experiment results, but once pass yielding point,

the von mises become constant (supposely the vonmises will increase with the updating trial stress)

Dear all I came up with some stress distributions which exist in a cylindrical specimen in a tensile test. However, I cannot understand how these formulas were gotten. There is a reference to a Bridgman paper (1944). Is there anyone who can give some inputs abouts this?

Thanks in advance 

Hi, i have problem with calling the principal values. The principal
values become very big values and make the excessive  element. There are
the coding i'm create as below: Any problem on it??



 







do k = 1, nblock

       

       

       s11(k,1) = stressOld(k,1) + dd11*strainInc(k,1)+

     1      dd12*strainInc(k,2)+ dd13*strainInc(k,3)

There are several possibilities for the realization of the presure load.

For
example, when I apply a pressure to an area (lets say, thin rectangular
plate) the area of the plate grows during the deformation process. One
possibility is to keep the pressure per unit area constant (in this case
the total force acting on a plate grows during the deformation) and the
second is to keep constant the total force acting on the plate (in this
case the force per unit area decreases with the deformation). I looked

Just like the above picture shows, when I use the Abaqus CEL technology to simulate the pile installation process,  the progaram can not run through. The whole step time is 100 and it can only run to 65. The desired penetration depth is 500 mm, however it stops at about 300 mm, I don't know why. Waiting for someone who is familiar with this area wo solve my puzzles.

Many thanks beforehand.

Hi, I'm modeling a composite box structure consisting of several fillet zones. Now I know only those fillet zones will develop progressive damage. The question is how I can apply USDFLD into only thiese zones, instead of making subroutine calculation of the whole model. I suppose there should be an argument to specify the range of elements  into subroutine calulation, anyone knows that? Thx

Hello Everyone,