Amit Acharya Xiaohan Zhang
(Chinese Annals of Mathematics, 36(B), 2015, 645-658. Proceedings of the International Conference on Nonlinear and Multiscale Partial Di fferential Equations: Theory, Numerics and Applications held at Fudan University, Shanghai, September 16-20, 2013, in honor of Luc Tartar.)
We discuss the relevance of non-metricity in a metric-affine manifold (a manifold equipped with a connection and a metric) and the nonlinear mechanics of distributed point defects. We describe a geometric framework in which one can calculate analytically the residual stress field of nonlinear elastic solids with distributed point defects. In particular, we use Cartan's machinery of moving frames and construct the material manifold of a finite ball with a spherically-symmetric distribution of point defects.
Hello everyone,
I am working on textile composites. I have to assign local material orientation for the fibers. I have come across *ORIENT subroutine in abaqus. But I am quite new to user subroutines. Is there any other way in which I can assign local material orientation to the fibers?
The fiber layout is such that it has linear as well as sine part. Can anyone give some idea on how to create *ORIENT for such fibers?
Thanks
One approach to helical strand (cable or overhead electrical conductor) bending analysis puts the emphasis on friction rather than on elastic curved rod behavior. Based on Coulomb’s laws of friction, it leads to stick-slip models where strand bending stiffness varies with imposed curvature (Papailiou, 1995). Such an approach can be traced back to a Ph.D. thesis by H. Ernst, in 1933. This work is in fact often referred to in cable analysis reports. An English translation (with a short presentation) of the dissertation analytical part is attached.
The in situ nanomechanics is an emerging field that investigates the mechanical properties and deformation mechanisms of nanoscale and nanostructured materials, by integrating the real-time mechanical testing inside electron microscope and the mechanics modeling with atomic resolution. It provides a powerful approach to "visualize" the intrinsic nanomechanical behavior of materials - seeing is believing.
In the context of a European project involving partners in France, Germany and Belgium, we are seeking a motivated post-doc to implement a saddle-point search method in a discrete dislocation dynamics code to study thermally-activated dislocation processes, such as cross-slip, in complex microstructures. The start date is October 2014 and the post-doc will be based in Lyon (Institut Lumière Matière) but with strong interactions with the Laboratoire d'Etude des Microstructures, CNRS/ONERA near Paris.
Computational modelling of materials behaviour
is becoming a reliable tool to underpin scientific investigations and to
complement traditional theoretical and experimental approaches. In cases where
an understanding of the dual nature of the structure of matter (continuous when
viewed at large length scales and discrete when viewed at smaller length scales) and
its interdependences are crucial, multiscale materials modelling (MMM)
