This revised and updated edition of a book first published in 1972 has kept the general features of the first edition but as could be expected after two decades there are also substantial differences. For instance optimal design has been completely deleted as the developments in this field have been so great that it warrants a book in itself. The fundamental concepts based on Drucker's postulate rather than those of Prager's assumptions function have been introduced. Problems of cyclic loading have been given some more extensive treatment, both in the general theory and in applications. General indications and references have been added for reinforced concrete plates and shells. A general presentation of the yield condition for both plates and shells has been included and the section on the influence of axial force in plates has been almost re-written. Finally, a chapter has been added exclusively devoted to the numerical approach to limit load and shake-down load evaluation. Like the previous edition the book is directed towards engineering applications. The theory is rigorously developed and is therefore of great use to engineering students in plastic limit analysis. Furthermore, applications to metal and reinforced concrete plates and shells and to metal disks are treated by both analytical and numerical approaches.
Limit and shakedown analysis for structures can provide a very useful tool for design and analysis of engineering structures. "Structural Plasticity - Limit, Shakedown and Dynamic Plastic Analyses of Structure" provides more general solutions of limit and shakedown analysis for structures by using a unified strength theory. A series of solutions of plates from circular, annular plates to rhombus plates and square plates, rotating discs and cylinders, pressure vessels are presented. These results encompass the Tresca-Mohr-Coulomb solution of structure as special cases. The unified solution, which cannot be obtained by using a single criterion, is suitable to more materials and structures. Maohong Yu is professor of Department of Civil Engineering at Xi'an Jiaotong University, China. He has authored 12 books including "Unified Strength Theory and Its Applications" and "Generalized Plasticity".
Since the middle of the 20th Century yield design approaches have been identified with the lower and upper bound theorem of limit analysis theory – a theory associated with perfect plasticity. This theory is very restrictive regarding the applicability of yield design approaches, which have been used for centuries for the stability of civil engineering structures. This book presents a theory of yield design within the original “equilibrium/resistance” framework rather than referring to the theories of plasticity or limit analysis; expressing the compatibility between the equilibrium of the considered structure and the resistance of its constituent material through simple mathematical arguments of duality and convex analysis results in a general formulation, which encompasses the many aspects of its implementation to various stability analysis problems. After a historic outline and an introductory example, the general theory is developed for the three-dimensional continuum model in a versatile form based upon simple arguments from the mathematical theory of convexity. It is then straightforwardly transposed to the one-dimensional curvilinear continuum, for the yield design analysis of beams, and the two-dimensional continuum model of plates and thin slabs subjected to bending. Field and laboratory observations of the collapse of mechanical systems are presented along with the defining concept of the multi-parameter loading mode. The compatibility of equilibrium and resistance is first expressed in its primal form, on the basis of the equilibrium equations and the strength domain of the material defined by a convex strength criterion along with the dual approach in the field of potentially safe loads, as is the highlighting of the role implicitly played by the theory of yield design as the fundamental basis of the implementation of the ultimate limit state design (ULSD) philosophy with the explicit introduction of resistance parameters. Contents 1. Origins and Topicality of a Concept. 2. An Introductory Example of the Yield Design Approach. 3. The Continuum Mechanics Framework. 4. Primal Approach of the Theory of Yield Design. 5. Dual Approach of the Theory of Yield Design. 6. Kinematic Exterior Approach. 7. Ultimate Limit State Design from the Theory of Yield Design. 8. Optimality and Probability Approaches of Yield Design. 9. Yield Design of Structures. 10. Yield Design of Plates: the Model. 11. Yield Design of Plates Subjected to Pure Bending. About the Authors Jean Salençon is Emeritus Professor at École polytechnique and École des ponts et chaussées, ParisTech, France. Since 2009 he has been a member of the Administrative Board of CNRS (Paris, France). He has received many awards including the Légion d’Honneur (Commander), Ordre National du Mérite (Officer) and Palmes Académiques (Commander). His research interests include structure analysis, soil mechanics and continuum mechanics.
Elastic, Plastic and Yield Design of Reinforced Structures presents a whole set of new results which have been published by the authors over the last 30 years in the field of continuum solid mechanics applied to the analysis and design of reinforced civil engineering structures. The focus is on the development and application of up-scaling/homogenization methods in the design of such composite structures, with a special emphasis on the plastic behavior and ultimate strength of materials. The specificity of the book is highlighted by at least two completely innovative concepts which lie at the very heart of the book's originality: the elaboration of a fully comprehensive homogenization-based method for the design of reinforced structures (and not only materials), through the study of macroscopic behavior, and the development of a multiphase model for materials reinforced by linear inclusions, which considerably extends the range of applicability of the classical homogenization procedure. - Sums up almost thirty years of original research in the field of mechanics applied to the analysis and design of reinforced civil engineering structures - Focuses on the application of upscaling/homogenization methods to the design of civil engineering structures - Highlights the elaboration of a fully comprehensive homogenization-based method for the design of reinforced structures (and not only materials), through the concept of macroscopic behavior - Features development of a multiphase model for materials reinforced by linear inclusions, which considerably extends the range of applicability of the classical homogenization procedure.
Articles in this book examine various materials and how to determine directly the limit state of a structure, in the sense of limit analysis and shakedown analysis. Apart from classical applications in mechanical and civil engineering contexts, the book reports on the emerging field of material design beyond the elastic limit, which has further industrial design and technological applications. Readers will discover that “Direct Methods” and the techniques presented here can in fact be used to numerically estimate the strength of structured materials such as composites or nano-materials, which represent fruitful fields of future applications. Leading researchers outline the latest computational tools and optimization techniques and explore the possibility of obtaining information on the limit state of a structure whose post-elastic loading path and constitutive behavior are not well defined or well known. Readers will discover how Direct Methods allow rapid and direct access to requested information in mathematically constructive manners without cumbersome step-by-step computation. Both researchers already interested or involved in the field and practical engineers who want to have a panorama of modern methods for structural safety assessment will find this book valuable. It provides the reader with the latest developments and a significant amount of references on the topic.
This book provides an overview of direct methods, such as limit and shakedown analysis, which are intended for avoiding cumbersome step-by-step calculations to determine the limit states of mechanical structures under monotone, cyclic or variable actions with unknown loading history. The book comprises several contributions that demonstrate how tremendous advances in numerical methods, especially in optimization, have contributed to the success of direct methods and their applicability to practical engineering problems in structural mechanics and mechanics of materials. The contents reflect the outcomes of the workshop “Direct Methods for Limit State of Materials and Structures,” held in Cosenza, Italy in June 2022.
This book is centred about the Principle of virtual work and the related method for mechanical modelling. It aims at showing and enhancing the polyvalence and versatility of the virtual work approach in the mechanical modelling process. The virtual work statement is set as the principle at the root of a force modelling method that can be implemented on any geometrical description. After experimentally induced hypotheses have been made on the geometrical parameters that describe the concerned system and subsystems, the method provides a unifying framework for building up consistently associated force models where external and internal forces are introduced through their virtual rates of work. Systems described as three-dimensional, curvilinear or planar continua are considered: force models are established with the corresponding equations of motion; the validation process points out that enlarging the domain of relevance of the model for practical applications calls for an enrichment of the geometrical description that takes into account the underlying microstructure.
The theory of plasticity is a branch of solid mechanics that investigates the relationship between permanent deformation and load, and the distribution of stress and strains of materials and structures beyond their elastic limit. Engineering plasticity underpins the safety of many modern systems and structures. Realizing the full potential of materials as well as designing precise metal processing and energy absorption structures requires mastery of engineering plasticity. Introduction to Engineering Plasticity: Fundamentals with Applications in Metal Forming, Limit Analysis and Energy Absorption presents both fundamental theory on plasticity and emphasizes the latest engineering applications. The title combines theory and engineering applications of plasticity, elaborating on problem solving in real-world engineering tasks such as in metal forming, limit analysis of structures, and understanding the energy absorption of structures and materials. The five main parts of the book cover: Plastic properties of materials and their characterization; Fundamental theory in plasticity; Elastic-plastic problems and typical solutions; and Rigid-plastic problems under plane-stress conditions. This title provides students and engineers alike with the fundamentals and advanced tools needed in engineering plasticity. - Brings together plasticity theory with engineering applications and problem solving - Elaborates problem solving methods and demonstrates plasticity in various engineering fields - Covers the recent decades of research on metal forming and limit analysis - Includes energy absorption of new structures and materials where plasticity dominates analysis and design - Gives a systematic account of the theory of plasticity alongside its engineering applications
This book deals with the safety assessment of structures and structural components, possibly operating beyond the elastic limits under variable repeated thermo-mechanical loads. Examples of such situations can be found both in mechanical and civil engineering (e.g. transportation technologies, pressure vessels, pipelines, offshore platforms, dams, pavements and buildings in seismic zones). So-called "direct” methods are focused, based on the shakedown theorems and their specialisation to limit theorems. These methods are receiving increased attention for the prediction of structural failure because they provide the information that is essential in practice (e.g. safety factor and collapse mechanisms) by more economical procedures than step-by-step inelastic analysis; also, they only need a minimum of information on the evolution of loads as functions of time. The addressed audience are primarily engineers and scientists active in Structural Engineering and Safety and Reliability Analysis.
