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pressurization test

I am doing a simulation of a Prestressed concrete containment vessel for
internal pressurization test. currently i have made a 3D concrete model
and embedded a reinforcing structure and tendons into it using embedded
region option. but during analysis, it is showing that ratio of
deformation speed to wave propagation speed exceeded 1 in some elements
and the job is getting aborted. someone pls help me figure out what
could be the reason. I have attached my input file for
reference......thank you....

Zhigang Suo's picture

Who was PhD advisor of Prager?

I have been asking colleagues this question for some time.  I was a Ph.D. student of John W. Hutchinson, who was a Ph.D. student of Bernard Budiansky, who was a Ph.D. student of William Prager.  But for years, the Mathematics Genealogy Project listed the advisor for Prager as “unknown”.

Aaron Goh's picture

Purchase ABAQUS licence

Is it possible to buy an ABAQUS licence (or token) from another institution?  In Malaysia and Singapore, the sales of ABAQUS appear to be controlled by WorleyParsons who charge rather exorbitant prices on the licenses - e.g. I got the student edition from the web for USD99 but in Malaysia, the price sold by WorleyParsons is 3+ times more expensive.  I am thinking whether I can pay another institution for some tokens to run jobs.  Thanks.

The origin of "Progressive Damage Methodology"

Greetings, 

Recently I have been indulging into loads of papers on "Progressive Damage Methodology".

I wondered based on what theory did the "Progressive Damage Methodology" intrigue so many researchers to unfold various kind of experiment and simulation, in other words, why do people have to study on this methodology?

Also, I was curious on the difference between "Cumulative Damage" and "Progressive Damage".

Can anyone here possibly give me some advice on the two questions?

 Faithfully,

James

SivaSrinivasKolukula's picture

Seismic Analysis

Hi

     I am doing seismic analysis of Fluid filled cylindrical steel tanks using FEM. In this analysis I m supposed to find Base Shear and Overturning moment. Steel tank is thin shell and is flexible. For the complete loading of the shell I have its stress field i.e I have Nxx, Nxy, Nyy, Mxx, Mxy, Myy components of the thin shells middle surface. They are per unit length. Using these components how I can find Base Shear and OTM?

      Any reference/suggestion for this study....

Thanks in advance

Srinivas 

Ee Lian's picture

database on carbon/epoxy orthotropic prepreg

Hi all,

I 'm  interested in finding a complete seachable database on carbon/epoxy orthotropic prepreg [properties and values]. Those values are needed to be inputted into my finite element program for my thesis. One of those materials which i'm trying to find is the MR50/LTM25 as well as several others.

Any suggestions would be great

Thanks 

 

Kind regards,

Ee Lian

modelling and simulation of lspring damper system in ls dyna

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modelling and simulation of spring damper system in ansys ls dyna in drop test form plz guyss  help me out with this if any 1 can ................. regards

combining Abaqus/Standard and Abaqus/Explicit?

How can I run an analysis that starts in Abaqus/Standard and can be continued in Abaqus/Explicit? Does Abaqus automatically take care of data exchange between them or it should be manual. In other words, can I define step1 in a model run by Abaqus/Standard then immediately running step2 under Abaqus/Explicit?

Thanks,
Ahmad Falahatpisheh
PhD student of Mechanical and Aerospace Engineering
Edwards Lifesciences Center for Advanced Cardiovascular Technology
2141 Engineering Hall
University of California, Irvine

 

phunguyen's picture

A free program to generate interface elements in an existing FE mesh

Hello all,

Last year when I started implementing interface elements to model material failure, I realized that the formulation is easy except how to generate a mesh with interface elements. I did a googling to search for such a free program. Amazingly, I did not find any although there are many researchers working on the fracture mechanics field.

So, I wrote a small object-oriented C++ program which reads a FE mesh, duplicates nodes and insert interface elements where asked. The program is able to

(1) insert 1D/2D interface elements everywhere in a FE mesh

International Workshop On Advanced Materials for Wind Turbine Blades -23–26 February 2011, Cairo, Egypt

The Centre for Advanced Materials at the British University in Egypt is organizing an international workshop on Advanced Materials for Wind Turbine Blades. This workshop is partially funded by the European Commission under Eu-Egypt Innivation Fund and comes in collaboration with the International Institute for Multifunctional Materials for  Energy Conversion (IIMEC), Texas A&M, USA.

Micro Analysis of Composites in ansys

 Hi everybody, i am Ravikumar doing M. Tech. project on multi scale analysis of composites.

I gave the input as nodal displacements and different material properties for glass and resin. I applied all the normal stresses and shear stresses on the micro scale model which is of hexagonal array  structure. (i.e., one circular fiber at the centre and quarter fibers at the four corners of the model and the remaining portion is filled up by resin).

ABAQUS user material subroutine VUMAT and Eulerian mesh...

Hi there,

 Has anyone ever used a vumat subroutine with Eulerian elements? it seems that the stress update formulation is different from the way it is in Lagrangian approach! If you have any experience in this regard I'd highly appreciate if you share it with me.

 thanks

Surface mediated plasticity in sub-10-nm-sized gold crystals

Nature Communications 1, Article number:144 | DOI:10.1038/ncomms1149

Although deformation processes in submicron-sized metallic crystals are
well documented, the direct observation of deformation mechanisms in
crystals with dimensions below the sub-10-nm range is currently lacking.
Here, through in situ high-resolution transmission electron
microscopy (HRTEM) observations, we show that (1) in sharp contrast to
what happens in bulk materials, in which plasticity is mediated by
dislocation emission from Frank-Read sources and multiplication, partial
dislocations emitted from free surfaces dominate the deformation of

ansys

 

Hello every body.

                             i ve a very simple question regarding ansys. can anybody can suggest how to mesh the glued area.what is the best element to use for adhesive bonding for 2d case

Cohesive strength theory ?

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What is the “cohesive strength” theory?

What are the differences in the energy consumption processes near the tip of a crack in plain concrete, fibre reinforced concret

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What are the differences in the energy consumption processes near the tip of a crack in plain concrete, fibre reinforced concrete and metals?

Open hole shear strength test method

Hello

I am wondering test method about open hole specimen to acquire shear strength.

The specimen is made of composite and we tried to make fixture from ASTM D5379.

However the failure mode is not acceptable and I am thinking about new test method for

open hole specimen.

Let me know any idea to approach other test method to acquire open hole shear strength value.

Thanks

C.J. Syn

Sébastien Turcaud's picture

Inverse eigenstrain analysis based on residual strains in the case of small strain geometric nonlinearity

Hi,

I was wondering if someone knows literature related to "Inverse eigenstrain analysis based on residual strains in the case of small strain geometric nonlinearity"? (elongated bodies)

In the case of lineralized elasticity I guess one could postulate an eigenstrain distribution as the sum of a finite set of basic eigenstrain distribution and minimize the difference between the predicted and the actual residual strain distribution (retrieved from a synchroton mapping for example).

As done in the paper:

Python scripting

Hello

I am reading an abaqus odb which is solved for 2 time steps 'step1' and 'step2' and i want to read  the output at every last frame of these steps.  further, I have written python script to find change in dispacement. I have written this code which works fine to capture delta displacement

f1=odb.steps['step1'].frames[-1].fieldOutputs['U']
f2=odb.steps['step2'].frames[-1].fieldOutputs['U']

deltaf=f2-f1

shinubaby963's picture

Study material for Abaqus UMAT.........

Hai,

Does anyone have Abaqus Umat Study material. If so please give me.

 

Turning a shaft through conact pressure in ABAQUS/standard?

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Hello all,

This is my first post here. This seems be an informative and helpful forum.

I am trying to model the rotation of a "hard" shaft as a result of motion of 2 strips of soft materials (please see attached figure).

The strips are deformed due to external forces and as a result, contact pressures are applied on the shaft. The forces are then varied on the strips leading to net rotational forces on the shaft.

SiC tri-axial data

I want to simulate scracthing of SiC material using drucker-prager model.

Where can i get tri-axial data to get the parameters of drucker-prager?

Or is there any other way to define the parameters?

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