Download or read book Modeling Three dimensional Shape of Sand Grains Using Discrete Element Method written by Nivedita Das and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: The study of particle morphology plays an important role in understanding the micromechanical behavior of cohesionless soil. Shear strength and liquefaction characteristics of granular soil depend on various morphological characteristics of soil grains such as their particle size, shape and surface texture. Therefore, accurate characterization and quantification of particle shape is necessary to study the effect of grain shape on mechanical behavior of granular assembly. However, the theoretical and practical developments of quantification of particle morphology and its influence on the mechanical response of granular assemblies has been very limited due to the lack of quantitative information about particle geometries, the experimental and numerical difficulties in characterizing and modeling irregular particle morphology. Motivated by the practical relevance of these challenges, this research presents a comprehensive approach to model irregular particle shape accurately both in two and three dimensions. To facilitate the research goal, a variety of natural and processed sand samples is collected from various locations around the world. A series of experimental and analytical studies are performed following the sample collection effort to characterize and quantify particle shapes of various sand samples by using Fourier shape descriptors. As part of the particle shape quantification and modeling, a methodology is developed to determine an optimum sample size for each sand sample used in the analysis. Recently, Discrete Element Method (DEM) has gained attention to model irregular particle morphology in two and three dimensions. In order to generate and reconstruct particle assemblies of highly irregular geometric shapes of a particular sand sample in the DEM environment, the relationship between grain size and shape is explored and no relationship is found between grain size and shape for the sand samples analyzed. A skeletonization algorithm is developed in this study in order to automate the Overlapping Discrete Element Cluster (ODEC) technique for modeling irregular particle shape in two and three dimensions. Finally, the two-dimensional and three-dimensional particle shapes are implemented within discrete element modeling software, PFC2D and PFC3D, to evaluate the influence of grain shape on shear strength behavior of granular soil by using discrete simulation of direct shear test.

Download or read book Discrete Element Methods written by Benjamin K. Cook and published by . This book was released on 2002 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the Third International Conference on Discrete Element Methods, held in Santa Fe, New Mexico on September 23-25, 2002. This Geotechnical Special Publication contains 72 technical papers on discrete element methods (DEM), a suite of numerical techniques developed to model granular materials, rock, and other discontinua at the grain scale. Topics include: DEM formulation and implementation approaches, coupled methods, experimental validation, and techniques, including three-dimensional particle representations, efficient contact detection algorithms, particle packing schemes, and code design. Coupled methods include approaches to linking solid continuum and fluid models with DEM to simulate multiscale and multiphase phenomena. Applications include fundamental investigations of granular mechanics; micromechanical studies of powder, soil, and rock behavior; and large-scale modeling of geotechnical, material processing, mining, and petroleum engineering problems.

Download or read book Understanding the Discrete Element Method written by Hans-Georg Matuttis and published by John Wiley & Sons. This book was released on 2014-06-23 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gives readers a more thorough understanding of DEM and equips researchers for independent work and an ability to judge methods related to simulation of polygonal particles Introduces DEM from the fundamental concepts (theoretical mechanics and solidstate physics), with 2D and 3D simulation methods for polygonal particles Provides the fundamentals of coding discrete element method (DEM) requiring little advance knowledge of granular matter or numerical simulation Highlights the numerical tricks and pitfalls that are usually only realized after years of experience, with relevant simple experiments as applications Presents a logical approach starting withthe mechanical and physical bases,followed by a description of the techniques and finally their applications Written by a key author presenting ideas on how to model the dynamics of angular particles using polygons and polyhedral Accompanying website includes MATLAB-Programs providing the simulation code for two-dimensional polygons Recommended for researchers and graduate students who deal with particle models in areas such as fluid dynamics, multi-body engineering, finite-element methods, the geosciences, and multi-scale physics.

Download or read book Geomechanics from Micro to Macro written by Kenichi Soga and published by CRC Press. This book was released on 2014-08-26 with total page 1668 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geomechanics from Micro to Macro contains 268 papers presented at the International Symposium on Geomechanics from Micro and Macro (IS-Cambridge, UK, 1-3 September 2014). The symposium created a forum for the dissemination of new advances in the micro-macro relations of geomaterial behaviour and its modelling. The papers on experimental investigati

Download or read book Three dimensional Discrete Element Modeling of Tunneling in Sand written by ASM Masud Karim and published by . This book was released on 2005 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Modeling in Micromechanics via Particle Methods written by H. Konietzky and published by Routledge. This book was released on 2017-11-01 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Particle methods have seen increasing use in several engineering and scientific fields, both because of their unique modelling capabilities and the availability of the necessary computational power. This title focuses on their theory and application.

Download or read book Numerical Modeling in Micromechanics via Particle Methods 2004 written by Y. Shimizu and published by CRC Press. This book was released on 2004-09-15 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: The variety of applications of PFC has continued to increase in the ten years since the first release of these programs. This volume contains a collection of fifty-two papers selected for presentation at the 2nd PFC Symposium, held 27-29 October 2004, in Kyoto, Japan. These contributions cover a wide range of engineering applications and theoretica

Download or read book Multibody Dynamics written by Josep M. Font-Llagunes and published by Springer. This book was released on 2016-04-12 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book includes selected papers from the ECCOMAS Thematic Conference on Multibody Dynamics, that took place in Barcelona, Spain, from June 29 to July 2, 2015. By having its origin in analytical and continuum mechanics, as well as in computer science and applied mathematics, multibody dynamics provides a basis for analysis and virtual prototyping of innovative applications in many fields of contemporary engineering. With the utilization of computational models and algorithms that classically belonged to different fields of applied science, multibody dynamics delivers reliable simulation platforms for diverse highly-developed industrial products such as vehicle and railway systems, aeronautical and space vehicles, robotic manipulators, smart structures, biomechanical systems, and nanotechnologies.

Download or read book Proceedings of the 7th International Conference on Discrete Element Methods written by Xikui Li and published by Springer. This book was released on 2016-12-01 with total page 1414 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the latest advances in Discrete Element Methods (DEM) and technology. It is the proceeding of 7th International Conference on DEM which was held at Dalian University of Technology on August 1 - 4, 2016. The subject of this book are the DEM and related computational techniques such as DDA, FEM/DEM, molecular dynamics, SPH, Meshless methods, etc., which are the main computational methods for modeling discontinua. In comparison to continua which have been already studied for a long time, the research of discontinua is relatively new, but increases dramatically in recent years and has already become an important field. This book will benefit researchers and scientists from the academic fields of physics, engineering and applied mathematics, as well as from industry and national laboratories who are interested in the DEM.

Download or read book Computational Mechanics of Arbitrarily Shaped Granular Materials written by Siqiang Wang and published by Springer Nature. This book was released on 2024-01-17 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on discrete element methods for arbitrarily shaped granular materials, including super-quadric models, spherical harmonic functions and level set methods, and numerical analysis of the flow characteristics of non-spherical granular materials. This book is used as a reference book for scientific researchers engaged in dynamic analysis of granular materials and optimal design of equipment structures in the fields of engineering mechanics, applied physics, mechanical engineering, and chemical engineering, as well as for graduate students or senior undergraduates of related majors in institutions of higher education.

Download or read book Imaging and Discrete Modelling of Sand Shape written by Riccardo Rorato and published by . This book was released on 2019 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: The shape of particles is known to play an important role in soil behaviour, with significant effects of engineering responses. Investigating how the shape of particles can be measured and quantified is therefore considered increasingly important in modern soil mechanics. This is propelled by the advent of computer based image-analyses and discrete modelling algorithms, which have opened new ways to tackle this problem. This work demonstrates how these two techniques can be made to work together.Image analyses are performed on x-rays micro-tomographs (μ-CT) of triaxial sand specimens, focusing on the characterisation and quantification of particle shapes. Two with very different particle shape sands are studied in details: Caicos ooids (rounded) and Hostun sand (angular). A discrete Digital Volume Correlation (DVC) algorithm is then used to track the kinematics of individual grains (around 50000 for each sand specimen) during the triaxial test and measure, with good precision, their cumulated displacements and rotations. Joint analysis of the shape and kinematic databases acquired is performed to find how particle shape descriptors are related to observed kinematics at the microscale level. It appears that true sphericity is a good predictor of upper bound rotational restraint.Modelling is based on the Discrete Element Method (DEM). Models that introduce rolling resistance at the contact are widely employed in DEM simulations, these approaches offer substantial computational benefits at the prize of increased calibration complexity. In this work, the values of true sphericity obtained by image analysis of the grains, either directly by 3D acquisition or by correlation with simpler to obtain 2D shape measures, are used to establish mechanically equivalent rotational restrictions. An empirical relation between a contact parameter (rolling friction) and a 3D grain shape descriptor (true sphericity is first calibrated - using both specimen-scale and grain scale results from two triaxial tests in Hostun sand and Caicos ooids. It is then validated by simulating other triaxial tests (1) with the same sands, but in different conditions (2) with Ottawa sand, for which 3D grain images were also available for examination, and (3) with Ticino sand, for which only 2D grain images were available.Finally, results of large-scale DEM simulations on the Cone Penetration Test (CPT) - exploiting the new proposed contact model - are presented. Experimental data on the CPT performed in a Calibration Chamber (CC) comprised of Ticino sand are successfully fitted by the numerical penetration curves at different confining pressures and conditions. A parametric study about the influence of particle shape and particle shape variability put in evidence the strong-coupled effects of rolling and frictional resistances at the particles contacts. The work described in this thesis will ease the use of DEM for large-scale simulations of geotechnical engineering problems.

Download or read book Computational Mechanics of Discontinua written by Antonio A. Munjiza and published by John Wiley & Sons. This book was released on 2011-10-13 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanics of Discontinua is the first book to comprehensively tackle both the theory ofthis rapidly developing topic and the applications that span a broad field of scientific and engineering disciplines, from traditional engineering to physics of particulates, nano-technology and micro-flows. Authored by a leading researcher who has been at the cutting edge of discontinua simulation developments over the last 15 years, the book is organized into four parts: introductory knowledge, solvers, methods and applications. In the first chapter a short revision of Continuum Mechanics together with tensorial calculus is introduced. Also, a short introduction to the finite element method is given. The second part of the book introduces key aspects of the subject. These include a diverse field of applications, together with fundamental theoretical and algorithmic aspects common to all methods of Mechanics of Discontinua. The third part of the book proceeds with the most important computational and simulation methods including Discrete Element Methods, the Combined Finite-Discrete Element Method, Molecular Dynamics Methods, Fracture and Fragmentation solvers and Fluid Coupling. After these the reader is introduced to applications stretching from traditional engineering and industry (such as mining, oil industry, powders) to nanotechnology, medical and science.

Download or read book Modeling in Geotechnical Engineering written by Pijush Samui and published by Academic Press. This book was released on 2020-12-01 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modeling in Geotechnical Engineering is a one stop reference for a range of computational models, the theory explaining how they work, and case studies describing how to apply them. Drawing on the expertise of contributors from a range of disciplines including geomechanics, optimization, and computational engineering, this book provides an interdisciplinary guide to this subject which is suitable for readers from a range of backgrounds. Before tackling the computational approaches, a theoretical understanding of the physical systems is provided that helps readers to fully grasp the significance of the numerical methods. The various models are presented in detail, and advice is provided on how to select the correct model for your application. Provides detailed descriptions of different computational modelling methods for geotechnical applications, including the finite element method, the finite difference method, and the boundary element method Gives readers the latest advice on the use of big data analytics and artificial intelligence in geotechnical engineering Includes case studies to help readers apply the methods described in their own work

Download or read book Powders and Grains 2005 Two Volume Set written by R. Garcia-Rojo and published by Taylor & Francis. This book was released on 2005-07-01 with total page 1512 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the Fifth International Conference on the Micromechanics of Granular Media, Powders and Grains 2005. Powders and Grains is an international scientific conference held every 4 years that brings together engineers and physicists interested in the micromechanics of granular media.The book is a guide to the hotte

Download or read book Practice of Discrete Element Method in Soil Structure Interface Modelling written by Wan-Huan Zhou and published by Springer Nature. This book was released on 2022-08-12 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is related to a parametric study of the soil–structural interface shearing behavior based on the numerical simulations of interface shear test with DEM, which is conducted from the role of soil properties, particle properties and structural properties. To aid readers in easily understanding the generation, implementation of models and controlling modes, for each part, the relevant code is provided in the text, and the whole source code of model is given in Appendix to share with readers for practice. The book is intended for graduate-level teaching and research in soil mechanics and geotechnical engineering, as well as in other related engineering specialties. This book is also of use to industry practitioners due to the inclusion of real-world applications, opening the door to advanced courses on modeling within the industrial engineering and operations research fields.

Download or read book Soil Structure Interaction Underground Structures and Retaining Walls written by V.M. Ulitsky and published by IOS Press. This book was released on 2015-02-24 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: With construction techniques becoming ever more complex, and population pressure leading to the development of increasingly problematic sites, expertise in the area of soil structure interaction is crucial to architectural and construction industries worldwide. This book contains the proceedings of the ISSMGE Technical Committee 207 International Conference on Geotechnical Engineering - Soil Structure Interaction and Retaining Walls - held in St Petersburg, Russia, in June 2014. The conference was dedicated to the memory of the outstanding geotechnical expert Gregory Porphyryevich Tschebotarioff. Topics covered at the conference included: soil structure interaction, underground structures and retaining walls, site investigation as a source of input parameters for soil structure interaction, and interaction between structures and frozen soils. The papers included here are the English language papers. Papers presented by the authors in Russian are published by the Georeconstruction Institute of St. Petersburg.

Download or read book Analytical Methods in Petroleum Upstream Applications written by Cesar Ovalles and published by CRC Press. This book was released on 2015-04-02 with total page 2054 pages. Available in PDF, EPUB and Kindle. Book excerpt: Effective measurement of the composition and properties of petroleum is essential for its exploration, production, and refining; however, new technologies and methodologies are not adequately documented in much of the current literature. Analytical Methods in Petroleum Upstream Applications explores advances in the analytical methods and instrumentation that allow more accurate determination of the components, classes of compounds, properties, and features of petroleum and its fractions. Recognized experts explore a host of topics, including: A petroleum molecular composition continuity model as a context for other analytical measurements A modern modular sampling system for use in the lab or the process area to collect and control samples for subsequent analysis The importance of oil-in-water measurements and monitoring The chemical and physical properties of heavy oils, their fractions, and products from their upgrading Analytical measurements using gas chromatography and nuclear magnetic resonance (NMR) applications Asphaltene and heavy ends analysis Chemometrics and modeling approaches for understanding petroleum composition and properties to improve upstream, midstream, and downstream operations Due to the renaissance of gas and oil production in North America, interest has grown in analytical methods for a wide range of applications. The understanding provided in this text is designed to help chemists, geologists, and chemical and petroleum engineers make more accurate estimates of the crude value to specific refinery configurations, providing insight into optimum development and extraction schemes.