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Adhesion between transferrable monolayer and substrate ?


Is there any research about  interfacial adhesion of  transferrable monolayers and substrates ? I found it's quite different from the rough surface model, because the monolayer is flexible enough to match the roughness of surface. Can one determine the separation value from the different roughness of pure substrate and substrate with a monolayer ?

Can someone give me some clue ? Thanks a lot!

FEM method for PDE

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Hi all,


I want to solve one second order nonlinear partial differential equation. Please see attachment for PDE. 

any FEM solver is avilable to solve this PDE.


thanks in advance.




Modeling anisotropy with abaqus


Is there anyone out there that can suggest a suitable subroutine in abaqus for modeling anisotropy. I know about the potential option in abaqus CAE that uses hill`s criteria to define different yield ratios in different directions but the aluminum alloy i`m working with is almost isotrop at yield limit but strongly anisotrop at ultimate tensile stress and in plastic strain . So i need to use a subroutine that takes all these properties into considration.

I appreciate any help

 Best Regards

 Ali Khajehgani

dabiao liu's picture

about critical thickness theory

who  can tell me more about the critical thickness theory ?I will be very excited if you   can introduce some reference to me.I know that critical thickness theory is solved rigorously and ursed to validated a useful approximation which is combined with slip distance theory modified for a finite structure size . (physical life review letters :elastic limit and strain hardening of thin wires in torsion)

The use of IOSO Optimization and ABAQUS at Civil Structures of NPP (from ABAQUS Users' Conference)

At the stage of NPP civil structure design for determination of stress-strain state (SSS) at static and dynamic loading ABAQUS is widely used. Hereto the floor response spectra are determined for calculation of loadings on the equipment at special dynamic impacts (seismic, air shock wave, aircraft crash). In case if the obtained characteristics of SSS or spectral accelerations exceed maximum permissible values, designers take actions on strengthening the corresponding structural components.

Are Linear and Angular Momenta Interconvertible?

To the best of my knowledge, the two momentum conservation principles, namely, the conservation of linear- and angular-momentum, operate completely independent of each other. For an isolated object, there is no possibility of conversion of one form of momentum to the other.

Meshing a block with spherical void inside in Ansys

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I have a squre block and inside it there is an sphere. I want to mesh
the whole assembly. I can mesh the sphere but when i try to mesh the
squre block with the spherical hole it cant mesh and says "it cant
select the source and target face". I also tried to devide it into 8
parts. That helped me to mesh the sphere but i cant mesh the squre with
spherical hole with that too. So please anyone can help me out.

Spectacular torsional-flexural autovibrations of a Volga bridge

The autovibrations of the bridge over Volga river in the city of Volgograd(Russia) were filmed (not by me) today on 05/21/2010. The amplitude reachedabout 1 m. The bridge opening was just six months ago...

Apparently, either the bridge frame drag was too high or torsional stiffness / damping too low.

Hyperelastic+ Damage with UMAT - Abaqus/Standard



 I have the following problem:

I want to implement a hyperelastic material model with a damage function (like the pseudo-elasticity of Ogden) by using a UMAT in Abaqus/Standard.

For this, in the first step I try to implement the damage of Ogden, which already exist in Abaqus/Standard.

But I don't know in which way I build the tangent stiffness matrix for this case (nonlinear and dependent of the history)

Do anywhere know a good literature in order to read and understand this issue?

Monte Carlo Simulation

Hello everyone,

I am new to probabilistic assessment methods of structures of various kinds, and I have encountered a paper which includes results of "Monte Carlo Simulation" and also fragility curves. Could someone please recommend to me some books, papers, or even links and sites from where I can learn more about this probabilistic method and for the derivation of fragility curves? My email is

Thank you very much in advance,

George Papazafeiropoulos

Displacement Controlled Geometric Nonlinear FEM

Hi I am working on numerical simulation of petroleum pipeline subjected to
seismic hazards. I have developed Geo-Nonlinear FEM code for load
controlled which i have compered with Ansys and it is working fine.
now i would like to apply fault  displacement for this i need to
convert my code to displacement controlled using penalty approach
but it is not converging. i will be very happy if any one can suggest
how i can over come this problem or plz sugest me some book or papre. here I am using Newton-Raphson method 


3D Doctor Tool



I hope this is the right forum to get some help for my work. 

I am looking at CT data (DICOM files) to make FEM models. To generate 3D surface/volumes for FEM, I was looking for softwares. They all are pretty expensive (4-10K USD). I have decide togo with Able Software's 3D-DOCTOR. I am lookign for some reviews or user experience or comments for this tool.




SOS.Do anyone have this paper?

I have looked for the paper "FASTRAN-II [microform] : a fatigue crack growth structural analysis program / J.C. Newman, Jr" for a long time ,but until now ,I have not found it.Is there anyone so kind to help me ??

Thanks a lot .

8th International Conference on Fatigue Damage of Structural Materials - Author Registration Deadline: 1 June

Don't forget! Accepted oral and poster presenters should register no later than 1 June 2010 to ensure that their material is included in the final program and the book of abstracts.  Non-registered presentations will be withdrawn from the conference after this date.  Please include your abstract reference number when completing your registration form.

FEM simulation on damage of brittle materials with Abaqus on mesoscale

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Hi, Smile

I'm a fresher in abaqus. Now I'm trying to simulate the damage of brittle kind of materials, like concrete with abaqus on mesoscale. But there are some problems now...

Shuozhi Xu's picture

The potential for Vanadium in molecular dynamic simulation

One of the most significant factors in molecular dynamic simulatin is to choose the proper potential. Recently, I did some searching jobs on Vanadium (V) potential and finally decided which potential I am going to use. Here is a simple summary:
A brief introduction of EAM, F-S and MEAM potentials for BCC transition metals

Structural thermal analysis in ANSYS

How can we perform first structural and then thermal analysis in ANSYS (version 12) ? All the examples show the sequence the other way. I can't go for Direct coupled method as the materials are elastic-plastic (plasticity is not supported by direct coupling elements).


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