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Elastic solution for a hole in an infinite space

Dear All,

the solution of an elastic half space subjected to any generalized load may be seen as the solution of another elastic problem, that is elastic space with an infinite length hole when the hole radius goes to infinite.

Is there a "general" solution for that elastic problem? For general I mean a solution that can be used e.g. like a kernel in a convolution operation.

Mike Ciavarella's picture

A "crazy" theory to explain the Rubinstein, Cohen & Fineberg’s Detachment fronts of friction

Recent experiments in sliding friction are a major embarassment for all present understanding of friction using Coulomb or Rice-Ruina-Dieterich-Prakash rate-state dependent theories, which are the subject of large research programs. In particular, Rubinstein et al; (Detachment fronts and the onset of dynamic friction. Nature 430, 1005—1009. 2004) suggest that the contact area is not significantly altered by the fast fronts which perhaps are only precursors to the most important "slow fronts" travelling at speeds about 1/10 of the Rayleigh speed.

The Department of Engineering Mechanics, University of Nebraska-Lincoln, invites applications for a Research Assistant Professor

To enhance its leadership position and focus for the future, UNL CoE is now deploying a new strategic approach in biomaterials, focusing on novel experiments and ground-breaking research. UNL external research funding has tripled in the last decade. The investment of these funds enables the university to support innovative research projects, hire top faculty and provide them with equipment and facilities to achieve their goals. 

Pradeep Sharma's picture

Open Faculty Position at University of Houston in Nanomechanics, Computational Materials Science

University of Houston
Department of Mechanical Engineering
Cullen College of Engineering
Faculty Position-Nano Mechanics, Nano Materials

A question about electric displacement intensity factor of interacting cracks in piezoelectric materials

I am working on the problem of interacting cracks in piezoelectric materials. Due to the interaction of cracks, I found a non-intuitive phenomenon that the electric displacement intensity factor of the crack for some interacting profiles may be negative under some loading conditions (a tensile stress and an applied electric displacement). However, under the same loading conditions, the electric displacement intensity factor can never be negative for a single crack problem.

Harley T. Johnson's picture

Call for Abstracts: SES2008 at the University of Illinois

Abstracts are now being accepted for the 2008 Society of Engineering Science Annual Technical Meeting, to be held October 12th-15th, 2008 at the University of Illinois at Urbana-Champaign.  The conference will feature more than 30 technical symposia in Applied Mathematics, Bioengineering, Dynamics, Fluid Mechanics, Imaging, Multiscale and Nanomechanics of Solids, Mechanics of Materials, etc., as well as special symposia in honor of the 2008 SES Medalists, listed at the conference website: .

cracking analysis OF a 3-points bended sandwich beam in the negative stressed area of the beam (above the neutral axis)


I'm looking for ideas-ways to model the above mentioned thema and solutions to overcome some obstacles. Here are some observations of mine:

1) Above the neutral axis of a bended beam the stress field is negative.Furthermore the traditional type of K factors estimation in Ansys is insufficient.The reason as i believe is that we haven't relative despacements of the crack nodes along  y(normal) axis.In contradiction we have shear desplacements.So i retrieve Ki nearly zero and Kii some noticable results.(using contact elements)

thermal analysis

What are the good books to refer for thermal analysis with practical applications.

Sakdirat Kaewunruen's picture

20th Australasian Conference on the Mechanics of Structures and Materials (ACMSM20)

20th Australasian Conference on the Mechanics of Structures and Materials (ACMSM20)

Toowoomba, Queensland, Australia, 2-5 December 2008

The 20th Australasian Conference on the Mechanics of Structures and Materials (ACMSM20) will be held at the University of Southern Queensland (USQ) Toowoomba, 2-5 December 2008. The conference will be hosted by the Faculty of Engineering and Surveying, University of Southern Queensland, Toowoomba, Queensland, Australia.

Postdoctoral/Research Scientist Position in Computational Mechanics in Vancouver, Canada

We are seeking a highly motivated individual to join our Vancouver research institute. This is a two-year industrial postdoctoral fellow position, which could lead to permanent employment.The successful incumbent will work with a multi-disciplinary team of scientists to develop computer models to predict mechanical properties of wood and paper products.

Markus J. Buehler's picture

Postdoc position available at MIT / bioinspired thermal management

A postdoctoral associate position at MIT is available immediately, focused on the analysis and development of bioinspired, adaptive thermal management structures, by using theoretical and atomistic multi-scale modeling and simulation.

Roozbeh Sanaei's picture

Why No New Einstein?!

My research topic is too different from string theory!. but i think this not so old opinion of Proff. Lee Smolin about world research system weaknesses is very beneficial to read. and have convincing arguments in neccessity of changes in this system. Read this. it is not related to string theory,

Roozbeh Sanaei, Cellular and molecular bioengineering, Bioengineering department, National university of singapore

Dean Eastbury's picture

Program available for 3rd IC Engineering Failure Analysis

The full program for the 3rd International Conference on Engineering Failure Analysis is available at Join your peers and take advantage of the 15% "early bird" discount by registering for this popular and well-received single stream meeting before 30 April. The conference takes place July 13-16 in the beautiful coastal town of Sitges, just a few miles from Barcelona's international airport. 

About the polycrystal plasticity

Hi everyone,

I am trying to build polycrystal plasticity model  by using UMAT subroutine in ABAQUS. As we know, the orientation of grain is always espressed by Euler's angles. What I want to know is  how to assign different initial orientations to different grains using Euler's angles in Umat subroutine. Could anybody tell me how to do? Is there any example ?

Many Thanks,


Zhigang Suo's picture

Elastic dielectrics, slides for a short tutorial

Rob Wood teaches a course on micro/nano robotics, and asks me to give a 30-minute tutorial on the theory of dielectric elastomer actuators (DEAs).  I attach my slides, which might be useful to you if you'd like to include this topic in your class.  The tutorial draws upon work in the literature, as well as recent work in my group:

Graduate Research Supplements (GRS) to Current ENG Awards to Broaden Participation

(This message was sent to iMechanica by Ken Chong, of the National Science Foundation).  This letter is to call your attention to an opportunity to broaden participation particularly of underrepresented students in Ph.D. programs in engineering through supplements to current research grants funded by the divisions in the Directorate for Engineering (ENG) at the National Science Foundation.

Amit Acharya's picture

Void expansion as wave phenomena - might damage evolution be mathematically related to fluid dynamics and turbulence?

The main idea is the following: a most natural mathematical setup for considering the motion of the void-solid interface of an expanding void is that of the traveling wave. Thus, a theory for macroscopic damage evolution may be suspected as being a homogenized version of basic theory that has such wave phenomena as an essential ingredient. This paper is a first step in probing such questions. 

Zhigang Suo's picture

6000 registered users of iMechanica

Early this week the number of registered users passed 6000.  Our growth rate remains nearly a constant, about 10 new users per day. In January Teng plotted some basic statistics of iMechanica


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