Douglas P Holmes's picture

Journal Club Theme of February 2012: Elastic Instabilities for Form and Function

Welcome to February 2012's Journal club, which will include a discussion on elastic instabilities for form and function. Not long ago, the loss of structural stability through buckling generally referred to failure and disaster. It was a phenomenon to be designed around, and rarely did it provide functionality*. The increasing focus on soft materials, from rubbers and gels to biological tissues, encouraged scientists to revisit the role of elastic instabilities in the world around us and inspired their utilization in advanced materials. Now the field of elastic instabilities, or extreme mechanics, brings together the disciplines of physics, mechanics, mathematics, biology, and materials science to extend our understanding of structural instabilities for both form and function. In this journal club, we're going to look at research on the wrinkling, crumpling, and snapping of soft or slender structures. 


marjan.oboudi's picture

Question PFC2D

I'm Trying to make a model using PFC2D software. Does anyone have an idea about how to rotate a combination of walls and balls. What I'm thinking about is to rotate all position vectors of all balls using "Rotation Matrix" but I don't know how can I start!

 I'm also looking for PFC2D Tutorials or any complementary examples.

 I would be thankful if you could help me?

  Marjan

McMaster University, Canada, ON.


Mike Ciavarella's picture

cracks in A380? Every plane now in the air is an experiment by itself...

 You may have heard of Qantas Airways and Korean Air will carry out inspections for wing cracks on their Airbus A380 superjumbo planes earlier than previously scheduled, after European air safety officials ordered global checks, warning of a safety risk if the defects were not fixed.

You can see a VIDEO here .


How do I delete my account?

Could someone please tell me how I delete my account? 


rena's picture

8th International Conference on Fracture Mechanics of Concrete and Concrete Structures, March 10-14,2013, Toledo-Spain

Dear Colleagues,
 
With this notice, I would like to call your attention for the ongoing Call for Papers for the FraMCoS-8, 8th International Conference on Fracture Mechanics of Concrete and Concrete Structures, that will take place in Toledo-Spain from 10 to 14 March 2013.
 
Abstracts will be accepted until 15 March 2012.
 
Individuals interested in organizing a session within the conference are also encouraged to submit their proposals as soon as possible. All detailed information about the conference is available in the FraMCoS-8 website at:
 
http://www.framcos8.org/
 


Alan R. S. Ponter's picture

Pleased to see

I'm pleased to see that over 600 of you have at least read some of my comments and I wouldn't be surprise if not all of you read through to the end.


Abaqus - modelling adhesive joint

Dear all,

I want to model two composite plates who are connected with an adhesive joint:

http://dl.dropbox.com/u/4629007/2012-02-09_145405.png

http://dl.dropbox.com/u/4629007/2012-02-09_145458.png

the upper and lower plate are modelled as composite plates while the vertical part on the right should represent the adhesive joint between them.

http://dl.dropbox.com/u/4629007/2012-02-09_145441.png

As you can see in the above picture, I moddeled all of them with shell elements. Now I 'm having some difficulties:


Mary Boyce and Huajian Gao elected to the National Academy of Engineering

National Academy of Engineering Elects

66 Members and 10 Foreign Associates

                   WASHINGTON — The National Academy of Engineering (NAE) has elected 66 new members and 10 foreign associates, announced NAE President Charles M. Vest today. This brings the total U.S. membership to 2,254 and the number of foreign associates to 206.


azadpoor's picture

Computational mechanics of cells, tissues, and biomaterials (ECOMASS 2012), DEADLINE EXTENDED to FEBRUARY 29

Deadline for submission of abstracts extended to February 29th.

As a part of ECCOMAS 2012 (European Congress on Computational Methods in Applied Sciences and Engineering)

Submit your Abstract (Choose mini-symposium MS114)


Catalin Pruncu's picture

Deadline extended for NT2F12 congress

Deadline extended for NT2F12 congress which will be held in Transilvania University of BRASOV.

Brasov is one of the largest and most cherished cities of the country. Surrounded on three sides by mountains, it was a perfect place for a medieval settlement.

The old city, founded by the Teutonic Knights in 1211, is one of the best preserved cities in all of Europe. It was thotoughly restored to the delight of an increasing number of tourist. It is the capital city of Brasov Country, in central Romania, in Transylvania, at the foot of the Carpathian Mountains. Brasov also makes a fabulous base for exploring the surrounding countryside where the air is clean and the people friendly.


pictures and data of crack propagation experiment or example

Hello,

I am looking for some data/pictures of crack propagation tests. More precisely, what I am looking for are test results of some 2D structure (or structures that can be modeled in 2D) where the experimenter has listed the geometry, material, loads and boundary conditions, and displayed photos of the crack that was observed propagating on loading the structure. Sort of like "heres a plate of dimensions a x b, made of material x, with an initial crack here, I now apply a load of magnitude M, and heres a picture of the crack that has propagated."

If load vs crack propagation distance is also available that would be fantastic.


Is there anybody who are still studying the elastic vibration theory?

    I'm a graduate student studying the coupled elastic vibration prolbem of structures and soils. However, I'm not very interested in that, as I think the practical coupled structure and soil vibration problem is totally inelastic, and I don't think it is of great importance to study the elastic case. 

   Is there anybody studying the vibration problem  here and can you tell me what's the importance of studying the elastic vibration problem? Are you interested in inelastic vibration prolbem?


Pradeep Sharma's picture

Opening for a Non-tenure-track Instructional Faculty

The Mechanical Engineering department at the University of Houston has an opening for a non-tenure track instructional faculty position.  The ideal candidate should be passionate about teaching will be expected to teach 3 undergraduate courses a semester and help with ABET. A competitive 9-month salary is expected and summer support is possible as well. Although the position is non-tenure track, our intention would be to hire someone for the long-haul. Applicants are expected to have a PhD in mechanical engineering and should be willing to cover a broad range of basic undergraduate classes. Preference will be given to applicants who have also obtained their undergraduate degree in the US. The expected start date is August of 2012.


composite laminates

hai,

my project is analysis of functionally graded plates for thermal loads using matlab in this regard i need certain basepaper regarding "bending,buckling and vibrational analysis of composite laminates(cross-ply & angle-ply)subjected to only thermal loads(i,e temperature increment) either constant or linear change using different theories as classical laminate plate theory(CLPT),first order shear deformation theory(FSDT) and zeroth-order shear deformation theory(ZSDT)"

if any have information or material about the mentioned topic kindly help me in this regard


How to update solution-dependat variable (SVARS) during iterations

Hello everyone,

 I am implementing a uel user subroutine in ABAQUS. This uel is for modeling contact in X-FEM framework. Thus, it's a nonlinear problem and I need to store some solution dependent variables during each iteration. I know I can store SDVs in SVARS. But this vector will update at the end of each step, and not during iterations. Anybody knows about this problem?

 I really appreciate if anybody can help me with this.

    Thanks

    Ehsan 


Meshing difficulty in viscoelastic constrained layer damping

Hi,

I am simulating constrained layer damping with viscoelastic layer in Abaqus.

Used 3D continuum element - C3D20R for base an face sheet and and same with hybrid 

formulation C3D20RH for visco tape.

In FE mesh, I tied the nodes (through tie constraint) of base with that of visco tape and 

also the visco tape with that of face sheet. But in the deformed mode shape, I am finding 

the visco tape fully penetrated inside the casing (I guess as there is no contact, only tie 


Benzeggagh-Kenane (BK) criteria

Dear all,

Can anyone tell what kind of value of power i need to use for a PU glue? At the moment i am using the Benzeggagh-Kenane (BK) criteria.

Or will it be better to use the power-law mixed mode criteria for a glued in rod in timber?

I look forward to receiving your answer,

Ronald


Advanced R&D Training “Innovative strategies for three dimensional modelling of fracture phenomena” 4-7 SEPTEMBER 2012

 

 INSAVALOR, the subsidiary of industrial development and further education of INSA Lyon and further education service of Grenoble INP offer throughout the year a high-level seminars based on the results of research laboratories schools.

These seminars in English or/and in French (with a duration of 2 to 4 days) are designed for global companies that wish to promote the development of skills of their executives, experts, specialists, researchers. 

 

Public Profile

Engineers R&D, teachers, researchers, PhD Students, Post-Doc Students

 Prerequisites


Robertt Valente's picture

Mini-Symposium on "Developments in Finite Element and Meshless Formulations Applied to Metal Forming Problems", on ECCOMAS 2012

Mini-Symposium on "Developments in Finite Element and Meshless Formulations Applied to Metal Forming Problems" (MS124), within the ECCOMAS 2012 International Conference, September 10-14, Vienna, Austria 

Mini-Symposium description

Numerical simulation analyses of metal forming processes involve a high level of complexity, from both fundamental and industrial application standpoints, requiring robust and comprehensive technology in order to achieve realistic solutions.


Internal strain energy and resonant/natural frequency: inversely correlated?

Hello all,

I must apologise in advance if this is a silly question—I'm a biologist, not an engineer. I am using FEA for a zoological biomechanics project to model structural performance of certain skeletal elements, and I have observed that, in one particularly spring-like bone, internal strain energy is tightly inversely correlated with resonant/natural frequency (free-free analysis in Abaqus). Is this relationship obvious to an engineer? In particular, is this relationship predicted by the equations describing springs or such things as tuning forks (formula given on this Wikipedia page: http://en.wikipedia.org/wiki/Tuning_fork)? 


Postdoctoral Research Assistant in Modelling Creep Damage

At Oxford University we are seeking to appoint a post doctoral Research Assistant to work on the modelling of cavity nucleation and growth in the heat affected zone of a welded component operating in the creep regime. A detailed advertisement and further particulars about the post can be found in the attached files.

Further Information can be obtained from Prof Alan Cocks - alan.cocks@eng.ox.ac.uk


Mubeen's picture

FEAP umat routines

Hi all,

I am using FEAP 8.2 in my university, and have to write a user material routine, but there is no clear guideline/example about which files to modify for this purpose. Sorry to say, the programmer's manual is very short, and very little detail is there.

The old tutorials/examples based on FEAP (7.x) are no longer helpful because the FEAP 8.2, 8.3 source code has changed considerably (atlease the files in user folder), hence the novice can get mad after trying for many weeks to figure out the way for doing this.


Nanshu Lu's picture

Call for abstract-ASME IMECE 2012 Track 9-35 Symposium on Integrated Structures and Materials in Advanced Technologies

Dear colleagues,

We would like to invite you to submit an abstract to a Symposium on Mechanics of Integrated Structures and Materials in Advanced Technologies at the ASME 2012 IMECE, to be held Nov 9-15, 2012, at Houston Texas. This symposium will be the seventh in such a symposium series organized by ASME Technical Committee of Integrated Structures since IMECE 2006. We hope you can join us and continue the success of this symposium series.

Deadline of abstract submission is Monday, 27 Feb. 2012.

Topics of interests include, but not limited to the following areas: 


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