The Role of Particle Shape in Granular Rheology and Jamming PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download The Role of Particle Shape in Granular Rheology and Jamming PDF full book. Access full book title The Role of Particle Shape in Granular Rheology and Jamming by Theodore A. Marschall. Download full books in PDF and EPUB format.
Author: Theodore A. Marschall Publisher: ISBN: Category : Languages : en Pages : 243
Book Description
"Granular materials, non-Brownian suspension, emulsions, and foams are a class of 'soft matter' systems where the dominant interaction between particles arises from direct contact and the particles are sufficiently macroscopic so that thermal fluctuations can be ignored. All of these systems undergo a similar transition from a flowing phase to a disordered solid phase known as the jamming transition, which has been found to share many characteristics with phase transitions in thermalized systems. Most work on granular media has focused on the idealized case of spherical particles. This work focuses on systems with elongated convex grains and several nonconvex grain shapes in two dimensions, using a simple model of frictionless particles in a viscous background medium. These systems are compressed isotropically and sheared continuously over a wide range of densities and strain rates, with a particular focus on the rotational degrees of freedom of anisotropic particles. We find that the jamming transition in systems with anisotropic particles is broadly similar to that of circular disks, though in several ways the limit of circular disks is singular. We identify a nonuniform distribution of contacts on the surfaces of anisotropic particles, both when compressed and sheared, with a peak that diverges in the circular limit. We find that systems of convex particles are hypostatic at jamming, having fewer constraints from contacts than internal degrees of freedom. This leads to modes of motion with zero cost to energy at jamming, but only for small displacements, so that the system remains rigid against macroscopic perturbations. In particular, we identify sliding modes for particles which have flat regions on their surfaces. When sheared, anisotropic particles develop orientational ordering, which usually depends non-monotonically on the packing density. In the limit approaching circular disks, the ordering jumps discontinuously at the jamming transition. We explain the ordering with a mean-field model of particle rotation, finding that it results from the shearing acting as an ordering field combined with local interactions between particles. Finally, we find similar orientational ordering in sheared systems of nonconvex particles, which is modified by the more complex local structures of such particles"--Pages x-xi.
Author: Theodore A. Marschall Publisher: ISBN: Category : Languages : en Pages : 243
Book Description
"Granular materials, non-Brownian suspension, emulsions, and foams are a class of 'soft matter' systems where the dominant interaction between particles arises from direct contact and the particles are sufficiently macroscopic so that thermal fluctuations can be ignored. All of these systems undergo a similar transition from a flowing phase to a disordered solid phase known as the jamming transition, which has been found to share many characteristics with phase transitions in thermalized systems. Most work on granular media has focused on the idealized case of spherical particles. This work focuses on systems with elongated convex grains and several nonconvex grain shapes in two dimensions, using a simple model of frictionless particles in a viscous background medium. These systems are compressed isotropically and sheared continuously over a wide range of densities and strain rates, with a particular focus on the rotational degrees of freedom of anisotropic particles. We find that the jamming transition in systems with anisotropic particles is broadly similar to that of circular disks, though in several ways the limit of circular disks is singular. We identify a nonuniform distribution of contacts on the surfaces of anisotropic particles, both when compressed and sheared, with a peak that diverges in the circular limit. We find that systems of convex particles are hypostatic at jamming, having fewer constraints from contacts than internal degrees of freedom. This leads to modes of motion with zero cost to energy at jamming, but only for small displacements, so that the system remains rigid against macroscopic perturbations. In particular, we identify sliding modes for particles which have flat regions on their surfaces. When sheared, anisotropic particles develop orientational ordering, which usually depends non-monotonically on the packing density. In the limit approaching circular disks, the ordering jumps discontinuously at the jamming transition. We explain the ordering with a mean-field model of particle rotation, finding that it results from the shearing acting as an ordering field combined with local interactions between particles. Finally, we find similar orientational ordering in sheared systems of nonconvex particles, which is modified by the more complex local structures of such particles"--Pages x-xi.
Author: Bernard Cambou Publisher: Springer ISBN: 370912526X Category : Technology & Engineering Languages : en Pages : 403
Book Description
This book presents a complete and comprehensive analysis of the behaviour of granular materials including the description of experimental results, the different ways to define the global behaviour from local phenomena at the particle scale, the various modellings which can be used for a D.E.M. analysis to solve practical problems and finally the analysis of strain localisation. The concepts developed in this book are applicable to many kinds of granular materials considered in civil, mechanical or chemical engineering.
Author: Andrea J. Liu Publisher: CRC Press ISBN: 1482268175 Category : Science Languages : en Pages : 576
Book Description
The subject of jamming and rheology is a broad and interdisciplinary one that is generating increasing interest. This book deals with one of the oldest unsolved problems in condensed matter physics - that of the nature of glass transition in supercooled liquids. Jamming and Rheology is a collection of reprinted articles from several fields, ran
Author: Publisher: ISBN: Category : Languages : en Pages : 164
Book Description
An existing two dimensional Discrete Element numerical model which incorporates elliptical particles is used to simulate the biaxial shear of particulate systems. Comparisons are made with physical tests on circular and oval shaped rod systems. Good quantitative agreement was found with the circular rod data, but significantly weaker and softer response was found compared with the oval rod data. This discrepancy is attributed to differences in particle shape in the physical and numerical tests. Additional simulations were conducted using bedded, strongly anisotropic systems at varying degrees of particle flatness. These exhibit distinctly different stress strain and strength behavior, as well as different controlling mechanisms, as function of particle flatness and bedding plane orientation. Shear bands were observed in some flatness and bedding combinations. Interparticle interlocking, dilatancy and inhibition of particle rolling were all observed. Samples with bedding normal to the principal stress direction exhibited the highest shear resistance, as well as largest dilatancy. In systems composed of flat particles with bedding parallel to one of the planes of maximum obliquity, shear bands sometimes formed in the maximum obliquity plane opposite to the bedding plane.
Author: Scott Arthur Publisher: Springer Nature ISBN: 9819938260 Category : Technology & Engineering Languages : en Pages : 465
Book Description
This book consists of select proceedings of the 6th International Conference on Advances in Civil Engineering (ICACE 2022), covering various fields of civil engineering. Various topics covered in this book are construction and building materials, eco-friendly ground improvement, waste disposal technique, waste management, the durability of different concrete structures, environmental impact studies in relation to covid-19 pandemic, various aspects of foundation engineering, transport planning scenario in developing countries, highway materials and many more. The book will be for researchers and professionals working in the area of civil engineering.
Author: Qicheng Sun Publisher: WIT Press ISBN: 1845646444 Category : Technology & Engineering Languages : en Pages : 209
Book Description
Focussing on the basic mechanics and underlying physics of granular material, Mechanics of Granular Matter starts with an introduction to contact mechanics of individual particles before moving on to a discussion of the structure of force chain networks and the influence on bulk mechanical properties of granular solids and granular flows. Furthermore, a preliminary multi scale framework is proposed for the nonlinear mechanics and strain localization in granular materials.