Download or read book Speed Effects on Moving Cracks in Nonlinear ductile Materials written by Jian Wu and published by . This book was released on 2014 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: Speed effects on moving cracks in ductile or nonlinear materials are studied with newly developed theoretical models in the present thesis. Speed-dependent stress field, traction distribution and fracture energy are discussed in detail in four chapters. 1) An asymptotic analysis near the tip of a steady-state moving crack in a compressible hyperelastic material is given based on a finite plane strain model. The crack tip deformation and stress fields are derived up to the third order which meets the strict positivity of Jacobian determinant in the vicinity of the moving crack tip. Comparison with the experimental data shows that the crack-face profile and the energy release rate predicted by the present model are in reasonable agreement with experiments and several recent nonlinear elastic models. In addition, the crack branching angle predicted by the present model also agrees well with some known experimental data. 2) Steady-state moving crack under mode-I loading is studied with a modified cohesive zone model which addresses speed-dependent role of the normal stress parallel to the crack axis and the non-uniformity of traction force in cohesive zone. Unlike the classical Dugdale model which predicts independence of the cohesive zone length on crack speed, the present modified model predicts that the cohesive zone length strongly depends on crack speed. Comparison with some known experimental data suggests that the present modified model has the potential to capture the speed effects on moving cracks in ductile materials especially at high crack speed. 3) The modified cohesive zone model is then applied to a self-similar high-speed expanding crack problem. Numerical results show that the normal stress parallel to the crack face increases with increasing crack speed and can be even larger than the normal traction in the cohesive zone, which justifies the necessity of including the normal stress parallel to the crack faces in the yielding condition at high crack speed. Strain hardening effect is also examined based on a non-uniform traction distribution given by a polynomial whose coefficients are to be determined as part of the solution. 4) A simple mass-spring model is presented to study inertia effect of cohesive zone for a Yoffe-type mode-I steady-state moving crack of constant length. Traction distribution surrounding the cohesive zone and fracture energy at high crack speed are solved numerically by a proposed numerical method. Results show that fracture energy predicted by the present model increases significantly at high crack speed, which defines a limiting crack speed above that fracture energy tends to infinity. Reasonable agreement with some known experimental data suggests that the present model has the potential to catch inertia effect of cohesive zone of a high-speed moving crack which has not been considered by existing cohesive zone models. The theoretical models and numerical results achieved in this thesis contribute new ideas and insights into the study of high-speed dynamic fracture of nonlinear and ductile materials, and some results predicted by the present models provide plausible explanations for a few important phenomena of moving cracks at high crack speed which have not been well explained by the existing models.
Download or read book Cracks and Fracture written by K. Bertram Broberg and published by Elsevier. This book was released on 1999-02-24 with total page 771 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cracks and Fracture consists of nine chapters in logical sequence. In two introductory chapters, physical processes in the vicinity of the crack edge are discussed and the fracture process is described. Chapter 3 develops general basic concepts and relations in crack mechanics, such as path independent integrals, stress intensity factors and energy flux into the crack edge region. Chapters 4-7 deal with elastostatic cracks, stationary or slowly moving elastic-plastic cracks, elastodynamic crack mechanics and elastoplastic aspects of fracture, including dynamic fracture mechanics. Appendices include general formulae, the basic theory of analytic functions, introduction to Laplace and Hankel transforms and description of certain basic relations, for instance for stress waves in solids. There is an extensive bibliography, containing references to both classical and recent work, and a comprehensive index. Presents an extensive bibliography containing references to both classical and recent works and a comprehensive index Appendices include general formulas, the basic theory of analytic functions, introduction to Laplace and Hankel transforms, and descriptions of certain basic relations, for instance for stress waves in solids
Download or read book Dynamic Fracture Mechanics written by L. B. Freund and published by Cambridge University Press. This book was released on 1998-03-28 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume focuses on the development and analysis of mathematical models of fracture phenomena.
Download or read book Desiccation Cracks and their Patterns written by Lucas Goehring and published by John Wiley & Sons. This book was released on 2015-02-12 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bringing together basic ideas, classical theories, recent experimental and theoretical aspects, this book explains desiccation cracks from simple, easily-comprehensible cases to more complex, applied situations. The ideal team of authors, combining experimental and theoretical backgrounds, and with experience in both physical and earth sciences, discuss how the study of cracks can lead to the design of crack-resistant materials, as well as how cracks can be grown to generate patterned surfaces at the nano- and micro-scales. Important research and recent developments on tailoring desiccation cracks by different methods are covered, supported by straightforward, yet deep theoretical models. Intended for a broad readership spanning physics, materials science, and engineering to the geosciences, the book also includes additional reading especially for students engaged in pattern formation research.
Download or read book The Shock and Vibration Digest written by and published by . This book was released on 1984 with total page 594 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book IUTAM Symposium on Analytical and Computational Fracture Mechanics of Non Homogeneous Materials written by Bhushan L. Karihaloo and published by Springer Science & Business Media. This book was released on 2002-04-30 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume constitutes the Proceedings of the IUTAM Symposium on "Analytical and Computational Fracture Mechanics of Non-homogeneous Materials", held in Cardiff from 18th to 22nd June 2001. The Symposium was convened to address and place on record topical issues in analytical and computational aspects of the fracture of non-homogeneous materials as they are approached by specialists in mechanics, materials science and related fields. The expertise represented in the Symposium was accordingly very wide, and many of the world's greatest authorities in their respective fields participated. Given the extensive range and scale of non-homogeneous materials, it had to be focussed to enhance the quality and impact of the Symposium. The range of non-homogeneous materials was limited to those that are inhomogeneous at the macroscopic level and/or exhibit strain softening. The issues of micro to macro scaling were not excluded even within this restricted range which covered materials such as rock, concrete, ceramics and composites on the one hand, and, on the other, those metallic materials whose ductile fracture is strongly influenced by the presence of inhomogeneities. The Symposium remained focussed on fundamental research issues of practical significance. These issues have many common features among seemingly disparate non-homogeneous materials.
Download or read book Quasibrittle Fracture Mechanics and Size Effect written by Jia-Liang Le and published by Oxford University Press. This book was released on 2021-11-19 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many modern engineering structures are composed of brittle heterogenous, or quasibrittle, materials. These include concrete, composites, tough ceramics, rocks, cold asphalt mixtures, and many brittle materials at the microscale. Understanding the failure behavior of these materials is of paramount importance for improving the resilience and sustainability of various engineering structures including civil infrastructure, aircraft, ships, military armors, and microelectronic devices. Designed for graduate and upper-level undergraduate university courses, this textbook provides a comprehensive treatment of quasibrittle fracture mechanics. It includes a concise but rigorous examination of linear elastic fracture mechanics, which is the foundation of all fracture mechanics. It also covers the fundamental concepts of nonlinear fracture mechanics, and introduces more advanced concepts such as triaxial stress state in the fracture process zone, nonlocal continuum models, and discrete computational models. Finally, the book features extensive discussion of the various practical applications of quasibrittle fracture mechanics across different structures and engineering disciplines, and throughout includes exercises and problems for students to test their understanding.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1974 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanical Behavior and Fracture of Engineering Materials written by Jorge Luis González-Velázquez and published by Springer Nature. This book was released on 2019-08-29 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the theoretical concepts of stress and strain, as well as the strengthening and fracture mechanisms of engineering materials in an accessible level for non-expert readers, but without losing scientific rigor. This volume fills the gap between the specialized books on mechanical behavior, physical metallurgy and material science and engineering books on strength of materials, structural design and materials failure. Therefore it is intended for college students and practicing engineers that are learning for the first time the mechanical behavior and failure of engineering materials or wish to deepen their understanding on these topics. The book includes specific topics seldom covered in other books, such as: how to determine a state of stress, the relation between stress definition and mechanical design, or the theory behind the methods included in industrial standards to assess defects or to determine fatigue life. The emphasis is put into the link between scientific knowledge and practical applications, including solved problems of the main topics, such as stress and strain calculation. Mohr's Circle, yield criteria, fracture mechanics, fatigue and creep life prediction. The volume covers both the original findings in the field of mechanical behavior of engineering materials, and the most recent and widely accepted theories and techniques applied to this topic. At the beginning of some selected topics that by the author's judgement are transcendental for this field of study, the prime references are given, as well as a brief biographical semblance of those who were the pioneers or original contributors. Finally, the intention of this book is to be a textbook for undergraduate and graduate courses on Mechanical Behavior, Mechanical Metallurgy and Materials Science, as well as a consulting and/or training material for practicing engineers in industry that deal with mechanical design, materials selection, material processing, structural integrity assessment, and for researchers that incursion for the first time in the topics covered in this book.
Download or read book The Life of Cracks written by Srečko Glodež and published by Cambridge Scholars Publishing. This book was released on 2020-07-13 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many people find the concept of fracture and damage mechanics to be somewhat problematic, mainly because, until recently, close attention in mechanics was focused especially on the strength and resistance of materials. In this sense, to speak of fracture is as uncomfortable for some as it is to speak of a deadly disease. In confronting and preventing a fatal disease, one must understand its complexity, symptoms, and behavior; by the same token, in securing the strength of an engineering structure, one must understand the reasons and type of its potential failure. This book will provide knowledge and insights on this matter to its readers.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Engineered Materials Abstracts written by and published by . This book was released on 1995 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Japanese Science and Technology 1983 1984 written by United States. National Aeronautics and Space Administration. Scientific and Technical Information Branch and published by . This book was released on 1985 with total page 1080 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metals Abstracts written by and published by . This book was released on 1995 with total page 1192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamic Fracture written by K. Ravi-Chandar and published by Elsevier. This book was released on 2004-10-16 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic fracture in solids has attracted much attention for over a century from engineers as well as physicists due both to its technological interest and to inherent scientific curiosity. Rapidly applied loads are encountered in a number of technical applications. In some cases such loads might be applied deliberately, as for example in problems of blasting, mining, and comminution or fragmentation; in other cases, such dynamic loads might arise from accidental conditions. Regardless of the origin of the rapid loading, it is necessary to understand the mechanisms and mechanics of fracture under dynamic loading conditions in order to design suitable procedures for assessing the susceptibility to fracture. Quite apart from its repercussions in the area of structural integrity, fundamental scientific curiosity has continued to play a large role in engendering interest in dynamic fracture problems In-depth coverage of the mechanics, experimental methods, practical applications Summary of material response of different materials Discussion of unresolved issues in dynamic fracture
Download or read book Extended Finite Element Method for Crack Propagation written by Sylvie Pommier and published by John Wiley & Sons. This book was released on 2013-03-04 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: Novel techniques for modeling 3D cracks and their evolution in solids are presented. Cracks are modeled in terms of signed distance functions (level sets). Stress, strain and displacement field are determined using the extended finite elements method (X-FEM). Non-linear constitutive behavior for the crack tip region are developed within this framework to account for non-linear effect in crack propagation. Applications for static or dynamics case are provided.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1997 with total page 940 pages. Available in PDF, EPUB and Kindle. Book excerpt:
