A Paper about J. Den Hartog's Views about S.P. Timoshenko
My paper about the views of J. Den Hartog about S.P. Timoshenko has been published.
Will be pleased to hear your comments.
research
Symplectic Analysis of Wrinkles in Elastic Layers with Graded Stiffnesses
Wrinkles in layered neo-Hookean structures were recently formulated as a Hamiltonian system by taking the thickness direction as a pseudo-time variable. This enabled an efficient and accurate numerical method to solve the eigenvalue problem for onset wrinkles. Here, we show that wrinkles in graded elastic layers can also be described as a time-varying Hamiltonian system. The connection between wrinkles and the Hamiltonian system is established through an energy method.
Elaborating the controversy on the contribution of the surface stress in silicon nanowires
A link between the local surface stress at the atomic scale to the overall behavior of the continuum system indicates a twist deformation at the free end of silicon nano-cantilever. The importance of size and crystal orientation is demonstrated (for more details of the project see:https://www.researchgate.net/publication/327768951_Surface_Stress_Effec…).
Nanoindentation and nanoscratching at finite temperatures: Three reviews
Dear Colleague,
Dr. Saeed Zare Chavoshi and I have co-authored three review articles, concerning nanoindentation and nanoscratching at finite temperatures from the computational and experimental perspectives:
On mixed-mode fracture mechanics models for contact area reduction under shear load in soft materials
The fundamental problem of friction in the presence of macroscopic adhesion, as in soft bodies, is receiving interest from many experimentalists. Since the first fracture mechanics 'purely brittle' model of Savkoor and Briggs, models have been proposed where the mixed mode toughness is interpreted with phenomenological fitting coefficients introducing weaker coupling between modes than expected by the "purely brittle" model.
Journal Club for October 2018: Ruga mechanics of thin sheets: wrinkling, crumpling, and folding
Teng Zhang
Department of Mechanical and Aerospace Engineering, Syracuse University
Introduction
A phase field formulation for hydrogen assisted cracking [code included]
I hope some of you may find this work interesting, the finite element code developed (Abaqus UEL subroutine) can be downloaded from www.empaneda.com/codes
A phase field formulation for hydrogen assisted cracking
Emilio Martínez-Pañeda, Alireza Golahmar, Christian F. Niordson
Computer Methods in Applied Mechanics and Engineering, 342, pp. 742-761 (2018)
Plasticity implies the Volterra formulation: an example
A demonstration through an example is given of how the Volterra dislocation formulation in linear elasticity can be viewed as a (formal) limit of a problem in plasticity theory. Interestingly, from this point of view the Volterra dislocation formulation with discontinuous displacement, and non-square-integrable energy appears as a large-length scale limit of a smoother microscopic problem. This is in contrast to other formulations using SBV functions as well as the theory of Structured deformations where the microscopic problem is viewed as discontinuous and the smoother plasticity formulation appears as a homogenized large length-scale limit.