A state of stress in a body.  Components of stress.  Subject to a load, a body develops internal forces.  The distribution of the internal forces in the body is usually inhomogeneous. For example, when a rod is bent, part of the rod is in tension, and the other part of the rod is in compression.

If the internal forces are uniformly distributed in the body, the body is said to be in a homogeneous state of stress.  For brevity, we often say a state of stress, or just stress.

Subject to compression, elastic materials may undergo bifurcation of various kinds. A homogeneous material forms creases, whereas a bilayer consisting of a stiff film and a compliant substrate forms wrinkles. Here, we show several new types of bifurcation behavior for bilayers consisting of films and substrates of comparable elastic moduli. Depending on the ratios of moduli and thicknesses of the two materials, the critical strain for the onset of creases can be either smaller or larger than that for the onset of wrinkles.

Professor John Rogers, Swanlund Chair Professor of Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, was recently elected to the National Academy of Sciences. Congratulations to John!

Here is the link to the NAS press release: http://www.nasonline.org/news-and-multimedia/news/april-28-2015-NAS-Election.html

Dear all,

I am using Abaqus/explicite. My material definition is elasto plastic with stress strain values up to strain of 15!. After borthering tries now I think if I can set "Shear Failure Criteria Element Deletation option", it is possible to avoid this error. But I cannot find this option. Could someone guide me what exactly should I do in order to add distorted element deletation option and how? (an step-by-step tutorial will be approciate)

More Explanation about process:

Up to 10 New Frontiers Fellowships, which provide structured post-doctoral career development pathways to permanent academic positions, are to be appointed in the Faculty of Engineering and the Environment, University of Southampton. Applications are invited from individuals who would strengthen any of our research themes, including Structures and Solid Mechanics, Computational Engineering, Materials and Surface Engineering, Acoustics, Geomechanics and Bioengineering.

Openings at Bioinspired Materials and Structures Lab of USC

The ability of amorphous intergranular films to mitigate damage formation at grain boundaries is studied with molecular dynamics simulations. We find that such films can alter both crack nucleation and crack growth rates by efficiently absorbing dislocations, with thicker films being more effective sinks.

The call for new PhD positions at the IMT Institute for Advanced Studies Lucca, Italy, is open:

http://www.imtlucca.it/phd/prospective/admission

with deadline for online applications the 29th of June 2015.

A description of the Curriculum in Computer Science and Systems Engineering is available at:

http://www.imtlucca.it/phd/2015-16/computer-science

The Annual Robert J. Melosh Competition for the Best Student Paper in Finite Element Analysis was held last Friday, April 24, on the campus of Duke University.  

The winner of the 2015 Melosh Medal is Maurizio Chiaramonte, from Stanford University, for his paper “The H-Version of the Method of Auxiliary Mapping for Higher Order Solutions of Crack Problems.”   

Maurizio was selected as the winner on the basis of both his written paper and his oral presentation.  The other finalists at the 2015 competition were: