The physics associated with self-affine crack formation and propagation is discussed. Some novel concepts are suggested for the mechanics of self-affine cracks. These concepts are employed to model the crack face morphology and, in turn, to solve various problems with self-affine cracks. It is shown that linear elastic fracture mechanics (LEFM) is a special case of self-affine crack mechanics and should be used only in length scales larger than the self-alfine correlation length. The theoretical results are confirmed by available experimental data.

We found that randomly folded thin sheets exhibit unconventional scale invariance, which we termed as an intrinsically anomalous self-similarity, because the self-similarity of the folded configurations and of the set of folded sheets are characterized by different fractal dimensions. Besides, we found that self-avoidance does not affect the scaling properties of folded patterns, because the self-intersections of sheets with finite bending rigidity are restricted by the finite size of crumpling creases, rather than by the condition of self-avoidance.

This paper presents a geometric discretization of elasticity when

the ambient space is Euclidean. This theory is built on ideas from

algebraic topology, exterior calculus and the recent developments

of discrete exterior calculus. We first review some geometric

ideas in continuum mechanics and show how constitutive equations

of linearized elasticity, similar to those of electromagnetism,

can be written in terms of a material Hodge star operator. In the

discrete theory presented in this paper, instead of referring to

Hi All :

I was wondering why some people prefer to use Non Local Model while some others use Implicit Gradient Model (which can be derived from Non Local Model) .

When implicit Gradient Model is itself derived from Non Local Model ,and its FE implimentation just involves an additional average to be calculated and what is the need to introduce gradient terms ??

Thanks Alot

Kapil 

A three-year
PhD studentship is available within the Glasgow Research Partnership in
Engineering (GRPE) as part of the Joint Research Institute in Mechanics of
Materials, Structures and Bioengineering at the University of Glasgow. 
The
specific goals of the PhD will be to manufacture MREs and determine the
influence of manufacture conditions on the micro-structure and magnetic-sensitivity
of the magnetorheological elastomers (smart material).

I am working on a project for a more efficient process for cleaning supe plastic forming dies. Currently, we are cleaning them manually with an electric drill motor and a brush on the end of that. This process is ergonomically doing a number on our employees, not say that the process is lengthy. Is there anyone that has had any luck with any other process cleaning dies? Thanks.....