JMPS link: https://www.sciencedirect.com/science/article/pii/S0022509619304405?dgcid=raven_sd_aip_email
Arxiv link to full text: https://arxiv.org/abs/1905.08485
An Adaptive Quasi-Continuum Approach for Modeling Fracture in Networked Materials: Application to Modeling of Polymer Networks
We present a one-dimensional variant of the Irving-Kirkwood-Noll procedure to derive microscopic expressions of internal contact force and moment in one-dimensional nanostructures. We show that these expressions must contain both the potential and kinetic parts: just the potential part does not yield meaningful continuum results. We further specialize these expressions for helically repeating one-dimensional nanostructures for their extension, torsion and bending deformation. As the Irving-Kirkwood-Noll procedure does not yield expressions of stiffnesses, we resort to a thermodynamic equilibrium approach to first obtain the Helmholtz free energy of the supercell of helically repeating nanostructures. We then obtain expressions of axial force, twisting moment, bending moment and the associated stiffnesses by taking the first and second derivatives of the Helmholtz free energy with respect to conjugate strain measures. The derived expressions are used in finite temperature molecular dynamics simulation to study extension, torsion and bending of single-walled carbon nanotubes and their buckling.
The article will soon appear in the Mathematics and Mechanics of Solids. The same can be accessed at the following link: https://www.researchgate.net/publication/337873624_Microscopic_definiti…
The Materials Theory Group at the School of Materials Engineering of Purdue University has a post-doctoral opening in the area of modeling of thermal transport in crystalline solids. The postdoc will use Boltzmann Transport Equation approach to investigate the phonon and electron thermal transport in crystalline solids with defects. Applicants with closely related theory background in physics, materials science, mechanical engineering, or other majors are encouraged to apply. The ideal candidate is one who is strongly interested in the fundamental concepts of thermal transport and related computational modeling, and must have excellent programming skills. To apply, please send a curriculum vita with list of publications and the names and contact information of two references to Professor Anter El-Azab (aelazab [at] purdue.edu). The cover letter should explain the relevance of the applicant background to the postdoc research topic above. This position is part of the DOE funded Energy Frontiers Research Center for Thermal Energy Transport under Irradiation (TETI), and the postdoc is expected to collaborate with a large team of theorists and experimentalists. The position is available now and will remain open until filled.
Hello everyone,
I have created a UMAT code for J2 elasto-plasticity with isotropic hardening for 3D solid elements.
At this point I would like to support also plane stress shell elements. What changes in the code are
suggested? The already implemented code, takes as input the strain tensor at time tn and the strain
increment tensor and updates the stress at time tn+1 and calculates the material Jacobian and
achieve quadratic convergence. The stress and strain tensors are manipulated as 6x1 vectors and the
Recently, there has been a growing interest in investigating the multi-functional properties of novel types of metamaterials, metastructures, and metacomposites based on triply periodic minimal surfaces (TPMS). TPMS have been discovered more than 160 years ago and thanks to additive manufacturing (3D printing) they become reality only recently and opend the doors for several applications.
How to provide a structure with a force lying on a fixed line?
We provide the answer to this question in our paper: Bigoni and Misseroni (2019) Structures loaded with a force acting along a fixed straight line, or the “Reut’s column problem”.
Journal of the Mechanics and Physics of Solids.
Enjoy watching our video below (would you have trouble playing video on YouTube, click here to watch it).
How a mass falls when attached to a flexible element with varying length?
We provide the answer to this question in our paper: Armanini, Dal Corso, Misseroni, Bigoni (2019) Configurational forces and nonlinear structural dynamics.
Journal of the Mechanics and Physics of Solids.
Enjoy watching our video below (would you have trouble playing video on YouTube, click here to watch it).
May a catastrophe machine be realized through an elastic continuous element?
We provide a positive answer to this question in our paper: Cazzolli, Misseroni, Dal Corso. Elastica catastrophe machine: theory, design and experiments. Journal of the Mechanics and Physics of Solids.
Enjoy watching our videos below (would you have trouble playing videos on YouTube, click here to watch them).
Mechanical mismatches between implanted electronics and biological tissues can lead to inaccurate readings and long-term tissue damage. Here, we show that functionalized multi-walled carbon nanotubes twisted into helical fibre bundles that mimic the hierarchical structure of muscle can monitor multiple disease biomarkers in vivo. The flexible fibre bundles are injectable, have a low bending stiffness and display ultralow stress under compression.
