This book presents the integrated approach of analysis and optimal design of structures. This approach, which is more convenient than the so-called nested approach, has the difficulty of generating a large optimization problem. To overcome this problem a methodology of decomposition by multilevel is developed. This technique, which is also suitable for implementation on parallel processing computers, has the advantage of reducing the size of the optimization problem generated. The geometric programming for both equality and inequality constraints is used in the optimization.
Minimum weight design of aerospace structres has evolved during the past two decades into a rather rigorous scientific discipline that permits the rational selection of structural configurations and materials for various design requirements. Because of the pertinence of this body of literature to the structural design of advanced aerospace vehicles, a comprehensive bibliography of published literature on optimim structural design has been compiled and reviewed herein. In Part 1, a critical historical review highlights the significant advances in the literature concerned with analytical optimum design techniques for various structural elements, materials and thermal protection systems. The annotated bibliography is contained in Part 2. In Part 3, the current state of the art of the theory of optimum structural and thermostructural design is assessed. Included are the derivation of design indices resulting from various design requirements, a generalized presentation of optimum design theory and preferred methods of presenting optimum design results. (Author).
This book helps designers and manufacturers to select and develop the most suitable and competitive steel structures, which are safe, fit for production and economic. An optimum design system is used to find the best characteristics of structural models, which guarantee the fulfilment of design and fabrication requirements and minimize the cost function. Realistic numerical models are used as main components of industrial steel structures. Chapter 1 containts some experiences with the optimum design of steel structures Chapter 2 treats some newer mathematical optimization methods. Chapter 3 gives formulae for fabrication times and costs. Chapters 4 deals with beams and columns. Summarizes the Eurocode rules for design. Chapter 5 deals with the design of tubular trusses. Chapter 6 gives the design of frame structures and fire-resistant design rules for a frame. In Chapters 7 some minimum cost design problems of stiffened and cellular plates and shells are worked out for cases of different stiffenings and loads. Chapter 8 gives a cost comparison of cylindrical and conical shells. The book contains a large collection of literatures and a subject list and a name index.
The use of novel materials and new structural concepts nowadays is not restricted to highly technical areas like aerospace, aeronautical applications or the automotive industry, but affects all engineering fields including those such as civil engineering and architecture. The included contributions highlight the latest developments in design and manufacturing. Most high-performance structures require the development of a generation of new materials, which can more easily resist a range of external stimuli or react in a non-conventional manner. Particular emphasis is placed on intelligent structures and materials as well as the application of computational methods for their modelling, control and management. The book also addresses the topic of design optimisation. Contributions cover numerical methods, different optimisation techniques and new software. Optimisation problems include those related to the size, shape and topology of structures and materials. Optimisation techniques have much to offer to those involved in the design of new industrial products, as the appearance of powerful commercial computer codes has created a fertile field for the incorporation of optimisation in the design process of all engineering disciplines. The performance of structures under shock and impact loads is another area covered. The increasing need to protect civilian infrastructure and industrial facilities against unintentional loads arising from accidental impact and explosion events as well as terrorist attacks is reflected in the sustained interest worldwide. While advances have been made in recent decades, many challenges remain, such as developing more effective and efficient blast and impact mitigation approaches or assessing the uncertainties associated with large and small scale testing and validation of numerical and analytical models. The overall aim is to move towards a better understanding of the critical issues relating to the testing behaviour, modelling and analyses of protective structures against blast and impact loading. The studies contained in this volume were presented at the International Conference on High Performance and Optimum Structures and Materials Encompassing Shock and Impact Loading and address issues involving advanced types of structures, particularly those based on new concepts, and shock and impact resistance.
Introduction to Optimum Design, Third Edition describes an organized approach to engineering design optimization in a rigorous yet simplified manner. It illustrates various concepts and procedures with simple examples and demonstrates their applicability to engineering design problems. Formulation of a design problem as an optimization problem is emphasized and illustrated throughout the text. Excel and MATLAB® are featured as learning and teaching aids. - Basic concepts of optimality conditions and numerical methods are described with simple and practical examples, making the material highly teachable and learnable - Includes applications of optimization methods for structural, mechanical, aerospace, and industrial engineering problems - Introduction to MATLAB Optimization Toolbox - Practical design examples introduce students to the use of optimization methods early in the book - New example problems throughout the text are enhanced with detailed illustrations - Optimum design with Excel Solver has been expanded into a full chapter - New chapter on several advanced optimum design topics serves the needs of instructors who teach more advanced courses
The use of novel materials and new structural concepts nowadays is not restricted to highly technical areas like aerospace, aeronautical applications or the automotive industry, but affects all engineering fields including those such as civil engineering and architecture. Addressing issues involving advanced types of structures, particularly those based on new concepts or new materials and their system design, contributions highlight the latest developments in design, optimisation, manufacturing and experimentation. Also included are contributions on new software, numerical methods and different optimisation techniques. Optimisation problems of interest involve those related to size, shape and topology of structures and materials. Most high performance structures require the development of a generation of new materials, which can more easily resist a range of external stimuli or react in a non-conventional manner. Particular emphasis is placed on intelligent structures and materials as well as the application of computational methods for their modelling, control and management. Optimisation techniques have much to offer to those involved in the design of new industrial products. The formulation of optimum design has evolved from the time it was purely an academic topic, able now to satisfy the requirements of real life prototypes. The development of new algorithms and the appearance of powerful commercial computer codes, with easy to use graphical interfaces, have created a fertile field for the incorporation of optimisation in the design process in all engineering disciplines. This proceedings volume is the first from a new edition of the High Performance Design of Structures and Materials and the Optimum Design of Structures conferences, which follows the success of a number of meetings that originated in 1989. Topics covered include: Composite materials & structures; Material characterisation; Experiments and numerical analysis; Steel structures; High performance concretes; Natural fibre composites; Transformable structures; Lightweight structures; Timber structures; Environmentally friendly and sustainable structures; Emerging structural applications; Optimisation in civil engineering; Evolutionary methods in optimisation; Shape and topology optimisation; Aerospace structures; Structural optimisation; Biomechanics application; Material optimisation; Life cost optimisation; Intelligence structures and smart materials.
General equations are developed for the design of efficient structures protected from thermal environments typical of those encountered in boost-glide or atmospheric-reentry conditions. The method is applied to insulated heat-sink stressed-skin structures and to internally cooled insulated structures. Plates loaded in compression are treated in detail. Under limited conditions of plate buckling, high loading, and short flight periods, and for aluminum structures only, the weights of both configurations are nearly equal. Load parameters are found and are similar to those derived in previous investigations for the restricted case of a constant equilibrium temperature at the outside surface of the insulation.
Detailing a number of structural analysis problems such as residual welding stresses and distortions and behaviour of thin-walled rods loaded in bending, this text also explores mathematical function minimization methods, expert systems and optimum design of welded box beams.
This book is dedicated to the study of an aeroelastic phenomenon of cable supported long span bridges known as flutter, and proposes very innovative design methodologies, such as sensitivity analysis and optimization techniques, already utilized successfully in automobile and aerospace industries. The topic of long-span suspension and cable-stayed bridges is currently of great importance. These types of bridge pose great technical difficulties due to their slenderness and often great dimension. Therefore, these bridges tend to have problems caused by natural forces such as wind loads, some of which we have witnessed in our history, and we are currently seeing a very high incidence of bridge construction to overcome geographical obstacles such as bays, straits, or great estuaries. Therefore, it seems very appropriate to write a book showing the current capability of analysis and design, when up until now, the information could only be found partially in technical articles. This book will be useful for bridge design engineers as well as researchers working in the field. This book only requires previous knowledge of structural finite element models and dynamics, and it is advisable to have some previous knowledge in bridge engineering. Nevertheless, this book is very self-contained in such a way that all the information necessary to understand the theoretical developments is presented without the need of additional bibliography.
