Three problems about of the shock waves

                                      for the curious students

Through this post I wish to share some recent results that provide new insights into the role of a defect-core in mechanics. Below is the abstract of the work, and the references and links to the preprints of articles. I look forward to your comments and suggestions.



Abstract:

Markus Buehler of MIT, Ioannis Chasiotis of UIUC, John Dabiri of Caltech, and Robert Wood of Harvard are among 100 recipients of this year’s Presidential Early Career Awards for Scientists and Engineers.  Congratulations!

A postdoctoral fellowship is available in the Duke Computational Mechanics Laboratory, beginning in September of 2009 (with flexibility on timing).  Funding for the fellowship concerns research in the simulation of large-scale fragmentation phenomena.  The ideal candidate will have experience in some combination of the following areas:

When a block of an elastomer is bent, the compressed surface may form a crease. This paper analyzes the critical condition for creasing by comparing the elastic energy in a creased body and that in a smooth body. This difference in energy is expressed by a scaling relation. Critical conditions for creasing are determined for elastomers subject to general loads and gels swelling under constraint. The theoretical results are compared with existing experimental observations.

Dear all,

     Many numerical implementation of plasticity model uses spectral decomposition to represent the Cauchy stress, elastic strain,  such that stress update algorithm is written in the principal directions. As a result, I wonder what makes it benefical to write the stress update algorithm in spectral form? 

 Thanks,

WaiChing Sun

http://www.eurodyn2011.org/

Researchers at Duke University are seeking applications for NRC research associates, to work with Professors David Stepp and John Dolbow.  The NRC program is unique in the sense that applicants have the opportunity to perform research on a program they design.  The positions are well-paid fellowships and are nominally for two years, extendable to a third.  

In my opioion, the traditional concrete model is taking the smeared cracking concept to deal with the tensile cracking and using the elastoplastic method to deal with the compressive softening.

We can find that recently the CDM based concrete model become a hot research subject.

But what are the advantages of the CDM-based?

Thank you very much!