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Mike Ciavarella's picture

Nature paper about mechanical metamaterials violating Betti's theorem

Maybe because I am proud of Betti's theorem being italian, I am curious about this big emphasys on systems violating it.  They may "open avenues for energy absorption, conversion and harvesting, soft robotics, prosthetics and optomechanics".... ?  I'd be curious to hear some comments.   Anyway, the last author Andrea Alu is anyway italian like Betti.

Prony series with temperature dependent stiffness

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Hello,

I have implemented a viscoelastic model (Simo/Hughes approach: Prony series for small strain)

in Abaqus using Umat and it works fine for dynamic isothermal simulations (I validated with the Prony series implemented in Abaqus).

Now, I want to consider thermal loads (I have temperature dependent stiffnesses from a DMA experiment).

How should I use these temperature dependent stiffnesses in the model?

A postdoctoral associate position at Department of Petroleum Engineering, Texas A&M University

A postdoctoral associate position is available at Department of Petroleum Engineering, Texas A&M University in the area of resistivity characterization of geomaterials. Experimental characterization at nano-scale will be combined with modeling techniques to get insight into electrical properties of geomaterials at fundamental length scales. 

On structured surfaces with defects: geometry, strain incompatibility, internal stress, and natural shapes

Given a distribution of defects on a structured surface, such as those represented by 2-dimensional crystalline materials, liquid crystalline surfaces, and thin sandwiched shells, what is the resulting stress field and the deformed shape? Motivated by this concern, we first classify, and quantify, the translational, rotational, and metrical defects allowable over a broad class of structured surfaces. With an appropriate notion of strain, the defect densities are then shown to appear as sources of strain incompatibility.

L.H.Poh's picture

Reserch Fellow Position in the National University of Singapore

 We are looking for a Research Fellow to work on the penetration resistance of concrete subjected to high velocity projectile impact (see description in attached file). To apply, please send a single pdf file including cover letter, cv, list of publications and the contact details of 2 references, to ceeplh@nus.edu.sg

Research scientist in computational mechanics of composite materials at Institute of High Performance Computing, A*STAR, Singapore

We are looking for capable and responsible candidates for a Research Scientist position in Computational Mechanics of Composite Materials:

  • PhD in Mechanical Engineering / Materials Science

bardia's picture

PhD/masters position in Mechanical Department at University of Hawaii at Manoa

A PhD/masters position is available in AMMI Lab at University of Hawaii at Manoa in the field of surgical robotics. Interested and outstanding candidates should visit my website at http://uhatmanoa.wixsite.com/ammi. Information about general admission process could be found on http://uhatmanoa.wixsite.com/ammi/prospective-students.

Wenbin Yu's picture

ASC 2017 Abstract due Feb. 17

Dear Fellow mechanicians, if your work is related with composites, you might want to consider presending your work on the American Society for Composites Annual Conference to be held on Purdue campus. The abstract is due this Friday (Feb. 17).

rami98's picture

Post-Doc Position Available in Computational Mechanics

A post-doctoral position is available in the Mechanics of Composite Materials (MCM) Lab at the Faculty of Engineering, Tel-Aviv University (TAU), Israel.

Learn fluid mechanics or thermodynamics ?

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saberelarem's picture

On a systematic approach for cracked rotating shaft study: breathing mechanism, dynamics and instability

We present a systematic approach to deal with the modelling and analysis of the cracked rotating shafts behaviour. We begin by revisiting

the problem of modelling the breathing mechanism of the crack. Here we consider an original approach based on the form we give to the energy of the system and then identify

the mechanism parameters using 3D computations with unilateral contact conditions on the crack lips. A dimensionless flexibility is identified which makes the application

Regression testing with the Command design pattern

Computational mechanics practitioners are not typically known for practising well-established software engineering techniques. That makes code developed by various research groups next to impossible to understand and modify.  I still see requests on iMechanica on how to implement Drucker-Prager models when every freshman student probably has their own implementation.  It is likely that the person who developed a particular code cannot themselves understand the code a few years after the relevant paper has been published.  

Drucker Prager Plasticity model

Hi All,

I am trying to code the Drucker prager plasticity model for the 2D plane strain case using consistent tangent modulus. I am using C++, therefore I would appreciate if anyone could share relevant materials which I could use and preferrably for the 2D case so it is not unnecessarily complicated.

 

Oleg Kirillov's picture

Call for abstracts: Mini-Symposium "Instabilities in Structural Mechanics and Fluid-Structure Interactions" at ESMC 2018

This is the first announcement of the

Mini Symposium "Instabilities in Structural Mechanics and Fluid-Structure Interactions"

Organizers:
Oleg Kirillov (Northumbria University, UK), Olivier Doare (ENSTA ParisTech, France)

In the frame of ESMC 2018 - 10th European Solid Mechanics Conference, July 2-6, 2018 Bologna, Italy

Mike Ciavarella's picture

3D Printing Grand Challenge

Abstract Submission Extended to March 1st 2017

More information

Michael A. McCarthy's picture

Marie Curie Early Stage Researcher (PhD student), Improving the crashworthiness of composite transportation structures

Applications are invited for a PhD position at the University of Limerick, Ireland, funded through the EU Marie Curie Early Stage Researcher Programme.

SALARY: €37,903 p.a. (plus family allowance of €4,589 p.a. where appropriate in accordance with Marie Skłodowska-Curie programme rules).

Topic: Development of discrete fastener-less joining technologies for impact protection devices

ASME 2017 IMECE: Fatigue and Fracture of Active Materials–Call for abstracts

Dear Colleagues:

Please, consider to attend the symposium entitled "Fatigue and Fracture of Active Materials" organized under track "Mechanics of Solids, Structures, and Fluids" in the International Mechanical Engineering Congress and Exposition (IMECE) ASME 2017 conference. The conference will be held in Tampa, Florida, November 6–9, 2017 (https://www.asme.org/events/imece).

Siva P V Nadimpalli's picture

PhD position in Prof. Nadimpalli's group at NJIT

Hello All,

There is a potential opening for a PhD student in Prof. Nadimpalli’s group at the New Jersey Institute of Technology starting from Fall2017. Candidates with good academic credentials and an interest to work in experimental research projects are encouraged to apply. Ideal candidate should have a master’s degree in mechanical/materials science/aerospace or related field with a good background in Solid Mechanics, Materials Science, and Experimental Methods (including but not limited to SEM, TEM, and nanofabrication methods).

Grants available EC funded "Materials resistant to extreme conditions for future energy systems", 12-14 June 2017, Kyiv - Ukraine

Dear colleagues,

I would like to inform you about a Works "Materials resistant to extreme conditions for future energy systems", 12-14 June 2017, Kyiv – Ukraine.

The Workshop is funded by the European Commission Enlargement Programme. There is no fee to attend.  Participants from the target countries* can apply for a Grant to cover their cost.  Eligible for Grants are those that work in or are citizens of a target country.

Soft Materials Mechanics and the 2017 ASME IMECE

Dear Colleagues,

The Soft Materials Mechanics Technical Committee (TC) is pleased to announce that the abstract submission process for the 2017 ASME IMECE in Tampa, FL is open. The TC symposium solicits abstracts from many disciplines represented from previous years (active materials, gels, biomaterials, 3D printing, and more) as well new subject areas and collaborations.

Issues with implementation of strain gradient plasticity framework of Niordson and Hutchinson (2003) in Abaqus UEL subroutine

I have implemented the rate-independent strain gradient plasticity framework of Niordson and Hutchinson (2003) in UEL. I was able to validate the results of the shear of infinitely wide thin layer between two rigid surfaces (Niordson and Hutchinson, 2003). However, the UEL subroutine fails to converge for the more complex problem of the shear of finite width slab. I suspect the convergence issues are arising out of internal elastic-plastic boundary conditions and the yield criteria. I have few doubts in this regard.

 

Issues with the implementation of Strain gradient plasticity framework of Niordson and Hutchinson (2003) in ABAQUS UEL

I have implemented the rate-independent strain gradient plasticity framework of Niordson and Hutchinson (2003) in UEL. I was able to validate the results of the shear of infinitely wide thin layer between two rigid surfaces (Niordson and Hutchinson, 2003). However, the UEL subroutine fails to converge for the more complex problem of the shear of finite width slab. I suspect the convergence issues are arising out of internal elastic-plastic boundary conditions and the yield criteria. I have few doubts in this regard.

 

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