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ABAQUS + gfortran (abaqus_v6.env)

Submitted by Timothy E. Kendon on
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Hi

has anyone succeeded in compiling and linking a user define subroutine (e.g. DISP) with gfortran in ABAQUS? I appreciate the issues of linking e.g DISP.obj (compiled with gfortran) with object files precompiled with ABAQUS, however, as long as all compilers  are set to target the same platform and architecture, for example i386 instruction set on Linux, then you should be able to link the files. So I feel it is not necessarily a lost cause.

Efficient preconditioner for Augmented Lagrangian

Submitted by tlaverne on
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Hi folks !

I have a question which is more mathematical than mechanical. However since it is to solve mechanical problem, one of you may have an answer !

I want to solve a non-linear problem with non-linear equality constrains and I'm using a augmented Lagrangian with a penalty regularization term that, as well known, spoils the condition number of my linearized systems (at each Newton iteration I mean). The bigger the penalty term, the worse the condition number is. Would someone know an efficient way to get rid of this bad conditioning in that specific case ?

Help: calculate elasticity tensor for hyperelastic material with plane stress configuration

Submitted by Haofei Liu on
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Dear all,

I am confused with the calculation of elasticity tensor of hyperelastic material in plane stress configuration. Your helps are very much appreciated. Below is my question:

Incompressible strain energy function is expressed as, saying, U=***+p(J-1).

Therefore, the second piola-kirchhoff stress is: S=***+pC^-1 (the Lagrange muliplier p is treated as an arbitrary constant here, right?).

Using the plane stress condition, S<33>=0 so that p is updated as a function of deformation.

ABAQUS embedded regions

Submitted by Yasmine.Abdin on
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Hello,
 
I am trying to find out if someone has information about the "embedded region" constraint in Abaqus. I am trying to model a very simple short fiber in a matrix (short cylinder inside a block). The model is purely elastic. The problem is, no matter how high I assign the values of the E modulus of fiber, I always get equivalent properties of composite (fiber + matrix) equal to matrix properties.
 

How to learn user subroutines in ABAQUS by FORTRAN?

Submitted by Lilia Wang on
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User subroutines in ABAQUS

I'm a freshman in biomechanic and apply to learn user subroutines in ABAQUS by FORTRAN.

I have installed the ABAQUS 6.11, VS2008 and IVF 11.1.

But I don't know how to call the subroutines in ABAQUS, so I will be very appreciate if someone give me some suggestion or simple tutorials about this.

THANKS!

Warpage prediction of laminated composite materials

Submitted by Xi Liu on
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composite material
Thermal stresses
laminates
warpage

Can anybody recommend some papers/books that discuss how to caculate thermal induced warpage of lamianted composite materials? Paper/books with detial caculation/derivation process are preferred. Thanks a lot!

About strain energy calculation in atomic scale simulation

Submitted by bahamute on
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Hi, everyone.

I'm curious about how to calculate strain energy of certain domain in material in atomic scale.

I know how to calculate virial stress. But I can't extend my idea and find any references.

Is there anyone who has computed strain energy of material in atomic scale?

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