fracture

Hello,

I have a PhD position available for a project involving the design of metamaterial unit cells for shock wave mitigation applications. The graduate research assistantship (GRA) position is for the University of Tennessee Space Institute (UTSI) which is a part of University of Tennessee Knoxville (UTK). The student will be located in Knoxville. Some important points are:

Dear colleagues,

Dear Colleagues,

The degradation of a structure, under various loading conditions, involves the progress of damage by initiation and growth of defects, such as microvoids and microcracks, and their coalescence into macrocracks. Thermodynamically, all damage mechanisms share a common feature at a much deeper level, which is dissipation of energy. Degradation processes are irreversible, meaning that they cause irreversible alteration to the system and the surroundings.

The USACM is happy to announce a virtual seminar this week on Wednesday, July 1st at 3pm Eastern.  The title of the seminar is "Examining Fracture Behavior in Heterogeneous Poro-Elastic Media from Nano to Macro-Scale".  An abstract of the talk is available here:

https://unsacm.memberclicks.net/assets/docs/Newell_2020.07.01_2pm.pdf

We have a number of seats available to anyone interested.  We just ask attendees to register at this page:

Twenty years in since their introduction, it is now plain that the regularized formulations dubbed as phase-field of the variational theory of brittle fracture of Francfort and Marigo (1998) provide a powerful macroscopic theory to describe and predict the propagation of cracks in linear elastic brittle materials under arbitrary quasistatic loading conditions. Over the past ten years, the ability of the phase-field approach to also possibly describe and predict crack nucleation has been under intense investigation.

Published in Extreme Mechanics Letters: https://doi.org/10.1016/j.eml.2020.100685. Catastrophic failure of materials and structures due to unstable crack growth could be prevented if fracture toughness could be enhanced at will through structural design, but how can this be possible if fracture toughness is a material constant related to energy dissipation in the vicinity of a propagating crack tip.

Safer batteries, more efficient gas-turbine engines and solar cells, all require better-engineered nanocomposite materials. There is a limitation though -- how to investigate the fracture mechanics of these materials? Machine learning can help us overcome this limitation.

Description:

The goal of this project is to investigate the multi-scale behaviour of clay rocks, going from microscopic to macroscopic scale, with application to underground drilling. The research will be based on multi-scale approach and numerical method allowing to model microstructure media in a double-scale framework (FEMxFEM). Please, see the full description in the attached file here below.

Abstract: Advanced machine learning methods could be useful to obtain novel insights into some challenging nanomechanical problems. In this work, we employed artificial neural networks to predict the fracture stress of defective graphene samples. First, shallow neural networks were used to predict the fracture stress, which depends on the temperature, vacancy concentration, strain rate, and loading direction.

Deadline for short abstract submission - February 15, 2020

https://lnkd.in/dQUgfhv

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

https://www.mdpi.com/1099-4300/21/12/1188

Dear iMechanicians,

Please find below a paper, co-authored with Ivan Cuesta and Norman Fleck, on the mode II fracture of elastic-plastic sandwich layers. The paper is part of the special issue in the Journal of Applied Mechanics dedicated to John Hutchinson's 80th anniversary and the Century Fracture Mechanics Summit.

The NUMISHEET conference series is the most significant international conference on the area of the numerical simulation of sheet metal forming processes. Within Numisheet 2020, we are organizing a mini symposium on “Challenges and Opportunities in Forming Aluminum”.

Dear colleagues,  We would like to make you aware of a mini-symposium we are organizing for WCCM-ECOMAS in 2020, to be held in Paris on July 19-24, 2020. The symposium is entitled "Computational Geomechanics", and focuses on modeling aspects related to geological materials.

Dear Colleagues,

We invite you to submit a paper to the 2020 Society for Experimental Mechanics (SEM) Annual Meeting in one of the many sessions in the Fatigue and Fracture Track. See below for further information on these sessions, and please forward this to others who may be interested.

I have an opening for a two-year postdoctoral fellowship at Duke University.  The project is a collaboration with experimentalists. and concerns problems in which fractures are driven by fluid flow through porous media.

The ideal candidate will have some background in finite element methods and mechanics, nonlinear coupled field problems, C++, and high-performance computing.  Experience with fracture mechanics is useful but not required.  

The fellowship can begin as soon as this September, 2019, with some flexibility on the start date.  

I hope some of you will find this work interesting. We present a new Weibull framework for cleavage fracture that incorporates strain gradient plasticity and can estimate the three parameters of Weibull-type models without any prior assumptions. A post-print is available at www.empaneda.com

Gradient-enhanced statistical analysis of cleavage fracture

Emilio Martínez-Pañeda, Sandra Fuentes-Alonso, CovadongaBetegón

European Journal of Mechanics - A/Solids 77, 103785 (2019)

Preprint here: https://www.researchgate.net/publication/333090377_A_Novel_Hybrid_Finite...

Preprint here: https://www.researchgate.net/publication/333260238_An_Adaptive_Quasi-Con...