Elastoplastic behavior has long been part of the constitutive models incorporated in most computer codes, used in the design of civil and mechanical engineering structures. Elastoplastic Modeling offers a compact presentation of the fundamentals of classical elastoplastic modeling, the basis for many engineering applications currently implemented. This book provides a general background to enhance understanding of the modeling assumptions that govern the rationales of these applications. With this understanding comes the ability to assess their validation range and propose possible improvements. An instructive approach replaces excessive mathematical developments with a semi-phenomenological method, where mathematical modeling is driven by − and derived from − experimental observations. A logical track is followed, starting from material behavior modeling and leading to the analysis of the anelastic response of systems, subjected to quasi-static loading processes.

Elastoplastic behavior has long been part of the constitutive models incorporated in most computer codes, used in the design of civil and mechanical engineering structures. Elastoplastic Modeling offers a compact presentation of the fundamentals of classical elastoplastic modeling, the basis for many engineering applications currently implemented. This book provides a general background to enhance understanding of the modeling assumptions that govern the rationales of these applications. With this understanding comes the ability to assess their validation range and propose possible improvements. An instructive approach replaces excessive mathematical developments with a semi-phenomenological method, where mathematical modeling is driven by − and derived from − experimental observations. A logical track is followed, starting from material behavior modeling and leading to the analysis of the anelastic response of systems, subjected to quasi-static loading processes.

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 viscoelasticity has been built up as a mechanical framework for modeling important aspects of the delayed behavior of a wide range of materials. This book, primarily intended for civil and mechanical engineering students, is devoted specifically to linear viscoelastic behavior within the small perturbation framework. The fundamental concepts of viscoelastic behavior are first presented from the phenomenological viewpoint of the basic creep and relaxation tests within the simple one-dimensional framework. The linearity and non-ageing hypotheses are introduced successively, with the corresponding expressions of the constitutive law in the form of Boltzmann’s integral operators and Riemann’s convolution products respectively. Applications to simple quasi-static processes underline the dramatic and potentially catastrophic consequences of not taking viscoelastic delayed behavior properly into account at the design stage. Within the three-dimensional continuum framework, the linear viscoelastic constitutive equation is written using compact mathematical notations and takes material symmetries into account. The general analysis of quasi-static linear viscoelastic processes enhances similarities with, and differences from, their elastic counterparts. Simple typical case studies illustrate the importance of an in-depth physical understanding of the problem at hand prior to its mathematical analysis.

Elastoplastic behavior has long been part of the constitutive models incorporated in most computer codes, used in the design of civil and mechanical engineering structures. Elastoplastic Modeling offers a compact presentation of the fundamentals of classical elastoplastic modeling, the basis for many engineering applications currently implemented. This book provides a general background to enhance understanding of the modeling assumptions that govern the rationales of these applications. With this understanding comes the ability to assess their validation range and propose possible improvements. An instructive approach replaces excessive mathematical developments with a semi-phenomenological method, where mathematical modeling is driven by − and derived from − experimental observations. A logical track is followed, starting from material behavior modeling and leading to the analysis of the anelastic response of systems, subjected to quasi-static loading processes.

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.

The scale that concerns the practitioner in mechanics is usually qualified as macroscopic. Indeed, applications are rarely much below the human scale, and in order to be relevant models must be constructed on a similar scale, several orders of magnitude greater than the objects that are normally attributed to the physicist's sphere of interest. The mechanicist is therefore aware of the limits of these models, no matter how elegant their mathematical formulation may be, when the time comes far experimental validation. The mechanicist has a deep concern for the microscopic phenomena at the heart of what is being modelled, exposed by the physicist's research, which can today explain a wide range of material behaviour. The aim of this book is to present the general ideas behind continuum mechanics, thermoelasticity and one-dimensional media. Our approach to constructing mechanical models and modelling forces is based upon the principle oi virtual work. There are several advantages to thismethod. To begin with, it clearly emphasises the key role played by geometrical modelling, leading to mechanically consistent presentations in a systematic way. In addition, by requiring rigorous thought and clear formulation of hypotheses, it identifies the inductive steps and emphasises the need for validation, despite its axiomatic appearance. Moreover, once mastered, it will serve as a productive tool in the reader's later research career. This duality is used in the chapter devoted to variational methods for the solution of thermoelastic problems.

The scale that concerns the practitioner in mechanics is usually qualified as macroscopic. Indeed, applications are rarely much below the human scale, and in order to be relevant models must be constructed on a similar scale, several orders of magnitude greater than the objects that are normally attributed to the physicist''s sphere of interest. The mechanicist is therefore aware of the limits of these models, no matter how elegant their mathematical formulation may be, when the time comes far experimental validation. The mechanicist has a deep concern for the microscopic phenomena at the heart of what is being modelled, exposed by the physicist''s research, which can today explain a wide range of material behaviour. The aim of this book is to present the general ideas behind continuum mechanics, thermoelasticity and one-dimensional media. Our approach to constructing mechanical models and modelling forces is based upon the principle oi virtual work. There are several advantages to thismethod. To begin with, it clearly emphasises the key role played by geometrical modelling, leading to mechanically consistent presentations in a systematic way. In addition, by requiring rigorous thought and clear formulation of hypotheses, it identifies the inductive steps and emphasises the need for validation, despite its axiomatic appearance. Moreover, once mastered, it will serve as a productive tool in the reader''s later research career. This duality is used in the chapter devoted to variational methods for the solution of thermoelastic problems.

Elastoplastic behavior has long been part of the constitutive models incorporated in most computer codes, used in the design of civil and mechanical engineering structures. Elastoplastic Modeling offers a compact presentation of the fundamentals of classical elastoplastic modeling, the basis for many engineering applications currently implemented. This book provides a general background to enhance understanding of the modeling assumptions that govern the rationales of these applications. With this understanding comes the ability to assess their validation range and propose possible improvements. An instructive approach replaces excessive mathematical developments with a semi-phenomenological method, where mathematical modeling is driven by − and derived from − experimental observations. A logical track is followed, starting from material behavior modeling and leading to the analysis of the anelastic response of systems, subjected to quasi-static loading processes.

Elastoplastic behavior has long been part of the constitutive models incorporated in most computer codes, used in the design of civil and mechanical engineering structures. Elastoplastic Modeling offers a compact presentation of the fundamentals of classical elastoplastic modeling, the basis for many engineering applications currently implemented. This book provides a general background to enhance understanding of the modeling assumptions that govern the rationales of these applications. With this understanding comes the ability to assess their validation range and propose possible improvements. An instructive approach replaces excessive mathematical developments with a semi-phenomenological method, where mathematical modeling is driven by − and derived from − experimental observations. A logical track is followed, starting from material behavior modeling and leading to the analysis of the anelastic response of systems, subjected to quasi-static loading processes.

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 viscoelasticity has been built up as a mechanical framework for modeling important aspects of the delayed behavior of a wide range of materials. This book, primarily intended for civil and mechanical engineering students, is devoted specifically to linear viscoelastic behavior within the small perturbation framework. The fundamental concepts of viscoelastic behavior are first presented from the phenomenological viewpoint of the basic creep and relaxation tests within the simple one-dimensional framework. The linearity and non-ageing hypotheses are introduced successively, with the corresponding expressions of the constitutive law in the form of Boltzmann’s integral operators and Riemann’s convolution products respectively. Applications to simple quasi-static processes underline the dramatic and potentially catastrophic consequences of not taking viscoelastic delayed behavior properly into account at the design stage. Within the three-dimensional continuum framework, the linear viscoelastic constitutive equation is written using compact mathematical notations and takes material symmetries into account. The general analysis of quasi-static linear viscoelastic processes enhances similarities with, and differences from, their elastic counterparts. Simple typical case studies illustrate the importance of an in-depth physical understanding of the problem at hand prior to its mathematical analysis.

Elastoplastic behavior has long been part of the constitutive models incorporated in most computer codes, used in the design of civil and mechanical engineering structures. Elastoplastic Modeling offers a compact presentation of the fundamentals of classical elastoplastic modeling, the basis for many engineering applications currently implemented. This book provides a general background to enhance understanding of the modeling assumptions that govern the rationales of these applications. With this understanding comes the ability to assess their validation range and propose possible improvements. An instructive approach replaces excessive mathematical developments with a semi-phenomenological method, where mathematical modeling is driven by − and derived from − experimental observations. A logical track is followed, starting from material behavior modeling and leading to the analysis of the anelastic response of systems, subjected to quasi-static loading processes.

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.

The scale that concerns the practitioner in mechanics is usually qualified as macroscopic. Indeed, applications are rarely much below the human scale, and in order to be relevant models must be constructed on a similar scale, several orders of magnitude greater than the objects that are normally attributed to the physicist's sphere of interest. The mechanicist is therefore aware of the limits of these models, no matter how elegant their mathematical formulation may be, when the time comes far experimental validation. The mechanicist has a deep concern for the microscopic phenomena at the heart of what is being modelled, exposed by the physicist's research, which can today explain a wide range of material behaviour. The aim of this book is to present the general ideas behind continuum mechanics, thermoelasticity and one-dimensional media. Our approach to constructing mechanical models and modelling forces is based upon the principle oi virtual work. There are several advantages to thismethod. To begin with, it clearly emphasises the key role played by geometrical modelling, leading to mechanically consistent presentations in a systematic way. In addition, by requiring rigorous thought and clear formulation of hypotheses, it identifies the inductive steps and emphasises the need for validation, despite its axiomatic appearance. Moreover, once mastered, it will serve as a productive tool in the reader's later research career. This duality is used in the chapter devoted to variational methods for the solution of thermoelastic problems.

The scale that concerns the practitioner in mechanics is usually qualified as macroscopic. Indeed, applications are rarely much below the human scale, and in order to be relevant models must be constructed on a similar scale, several orders of magnitude greater than the objects that are normally attributed to the physicist''s sphere of interest. The mechanicist is therefore aware of the limits of these models, no matter how elegant their mathematical formulation may be, when the time comes far experimental validation. The mechanicist has a deep concern for the microscopic phenomena at the heart of what is being modelled, exposed by the physicist''s research, which can today explain a wide range of material behaviour. The aim of this book is to present the general ideas behind continuum mechanics, thermoelasticity and one-dimensional media. Our approach to constructing mechanical models and modelling forces is based upon the principle oi virtual work. There are several advantages to thismethod. To begin with, it clearly emphasises the key role played by geometrical modelling, leading to mechanically consistent presentations in a systematic way. In addition, by requiring rigorous thought and clear formulation of hypotheses, it identifies the inductive steps and emphasises the need for validation, despite its axiomatic appearance. Moreover, once mastered, it will serve as a productive tool in the reader''s later research career. This duality is used in the chapter devoted to variational methods for the solution of thermoelastic problems.