Download or read book Minimum Weight Design of Structures Via Optimality Criteria written by Jaan Kiusalaas and published by . This book was released on 1972 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: The state of the art of automated structural design through the use of optimality criteria, with emphasis on aerospace applications is reviewed. Constraints on stresses, displacements, and buckling strengths under static loading, as well as lower bound limits on natural frequencies and flutter speeds are presented. It is presumed that the reader is experienced in finite element methods of analysis, but is not familiar with optimal design techniques.
Download or read book Structural Design via Optimality Criteria written by George I. N. Rozvany and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: "During the last two decades, research on structural optimization became increasingly concerned with two aspects: the application of general numeri cal methods of optimization to structural design of complex real structures, and the analytical derivation of necessary and sufficient conditions for the optimality of broad classes of comparatively simple and more or less ideal ized structures. Both kinds of research are important: the first for obvious reasons; the second, because it furnishes information that is useful in testing the validity, accuracy and convergence of numerical methods and in assess ing the efficiency of practical designs. {raquo} (Prager and Rozvany, 1977a) The unexpected death of William Prager in March 1980 marked, in a sense, the end of an era in structural mechanics, but his legacy of ideas will re main a source of inspiration for generations of researchers to come. Since his nominal retirement in the early seventies, Professor and Mrs. Prager lived in Savognin, an isolated alpine village and ski resort surrounded by some of Switzerland's highest mountains. It was there that the author's close as sociation with Prager developed through annual pilgrimages from Australia and lengthy discussions which pivoted on Prager's favourite topic of struc tural optimization. These exchanges took place in the picturesque setting of Graubunden, on the terrace of an alpine restaurant overlooking snow-capped peaks, on ski-lifts or mountain walks, or during evening meals in the cosy hotels of Savognin, Parsonz and Riom.
Download or read book Minimum Weight Design of Structures Via Optimality Criteria written by J. Kiusalaas and published by . This book was released on 1972 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Optimality Criteria Approach to the Minimum Weight Design of Aircraft Structures written by M. W. Dobbs and published by . This book was released on 1977 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research presented in this report is both a continuation and an extension of the optimality criteria approach to structural optimization reported in AFOSR-TR-75-1431. In the present study the optimality criteria method is extended to provide a capability for the automated minimum weight design of elastic, redundant structures composed of one-and two-dimensional structural elements and subjected to multiple, independent static loading conditions. The design variables are taken to be the thicknesses of the structural elements. These variables are constrained to be between specified maximum and minimum values, as are the internal stresses in each element and the nodal displacements of the structure. Results are presented to indicate both the excellent performance of the optimality criteria method and the wide range of structures which can be designed using the algorithm. Finally, the algorithm is extended to include the new (to automated design) and very important requirement that structural integrity under the applied loads be maintained given the presence of existing structural fatigue cracks. This requirement, which is cast in an energy format and incorporated in the design algorithm as an inequality constraint, is shown to have a dominant effect in the design of safe, minimum weight aircraft structures. (Author).
Download or read book Optimality Criterion Methods in Structural Optimization written by and published by . This book was released on 1982 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimization algorithms based on an optimal criterion to design a minimum weight structure are presented. The algorithms are derived for the direct design variable and the reciprocal design variable, and their relationship is discussed. The use of different algorithms and their effect on the convergence behavior is illustrated with sample problems. The presentation is limited to structures which can be analyzed by the finite element method and which are subjected to the constraints on stresses, displacements, minimum and maximum sizes and system stability. (Author).
Download or read book Optimality Criterion Methods in Structural Optimization written by N. S. Khot and published by . This book was released on 1982 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimization algorithms based on an optimal criterion to design a minimum weight structure are presented. The algorithms are derived for the direct design variable and the reciprocal design variable, and their relationship is discussed. The use of different algorithms and their effect on the convergence behavior is illustrated with sample problems. The presentation is limited to structures which can be analyzed by the finite element method and which are subjected to the constraints on stresses, displacements, minimum and maximum sizes and system stability. (Author).
Download or read book Use of Optimality Criteria Methods for Large Scale Systems written by L. Berke and published by . This book was released on 1974 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computer Aided Optimal Design Structural and Mechanical Systems written by Carlos A. Mota Soares and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1018 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the edited version of lectures and selected papers presented at the NATO ADVANCED STUDY INSTITUTE ON COMPUTER AIDED OPTIMAL DESIGN: Structural and Mechanical Systems, held in Tr6ia, Portugal, 29th June to 11th July 1986, and organized by CEMUL -Center of Mechanics and Materials of the Technical University of Lisbon. The Institute was attended by 120 participants from 21 countries, including leading scientists and engineers from universities, research institutions and industry, and Ph.D. students. Some participants presented invited and contributed papers during the Institute and almost all participated actively in discussions on scientific aspects during the Institute. The Advanced Study Institute provided a forum for interaction among eminent scientists and engineers from different schools of thought and young reseachers. The Institute addressed the foundations and current state of the art of essential techniques related to computer aided optimal design of structural and mechanical systems, namely: Vari ational and Finite Element Methods in Optimal Design, Numerical Optimization Techniques, Design Sensitivity Analysis, Shape Optimal Design, Adaptive Finite Element Methods in Shape Optimization, CAD Technology, Software Development Techniques, Integrated Computer Aided Design and Knowledge Based Systems. Special topics of growing importance were also pre sented.
Download or read book Optimal Structural Design written by Ronald A. Gellatly and published by . This book was released on 1971 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report considers the state of the art in methods of structural optimization. Mathematical programming based methods, while extremely successful with problems of moderate size tend to become prohibitively costly when applied to large scale structures. A novel approach to the weight optimization of indeterminate structures under multiple loading conditions with strength and displacement constraints has been developed and is presented herein. Using this method significant improvements in computational time have been achieved over direct numerical search methods. In some cases the numbers of iterations required to determine the least weight have been reduced by factors of over 20. The rate of convergence is independent of problem size permitting application to large scale structures. Examples of application of the new approach to a number of problems are included.
Download or read book Three Contributions to Minimum Weight Structural Optimization with Dynamic and Aeroelastic Constraints written by Stanford University. Department of Aeronautics and Astronautics and published by . This book was released on 1976 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contents: Weight Optimization Under a Flutter Constraint; Optimization of Structures Undergoing Harmonic or Stochastic Excitation; The Optimization of Structures with Complex Constraints via a General Optimality Criteria Method.
Download or read book Criteria and Methods of Structural Optimization written by Andrzej M Brandt and published by Springer Science & Business Media. This book was released on 1987-06-30 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended to serve all those who are interested in structural opti mization, whether they work in this field or study it for other purposes. Rapid growth of interest in the cognitive aspects of optimization and the increas ing demands that the present day engineer has to meet in modern design have created the need of a monographic treatment of the subject. The vast number and wide range of structural optimization problems formulated and investigated in the last twenty years call for an attempt to sum up the pres ent state of knowledge in this domain and to outline the directions of its further development. The present authors undertook this task, hoping that the result would stimulate further work towards finding new methods and solutions and increasing the range of applications of the optimization methods to structural design. The immediate aim of the book is to present the basic criteria and methods of optimization and to provide a reference guide to the most important publications in the field. 'The book consists of fourteen chapters. Chapter 1 introduces the basic concepts, definitions and assumptions relating to structural optimization. Chapter 2 gives the foundations of optimization for minimum elastic strain potential or maximum rigidity, and sets a basis for optimization of bar, plate and lattice structures. Chapter 3 presents criteria of strength design and their applications to plane structures.
Download or read book Structural Optimization written by M. Save and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: After the IUTAM Symposium on Optimization in Structural Design held in Warsaw in 1973, it was clear to me that the time had come for organizing into a consistent body of thought the enormous quantity of results obtained in this domain, studied from so many different points of view, with so many different methods, and at so many levels of practical applicability. My colleague and friend Gianantonnio Sacchi from Milan and I met with Professor Prager in Savognin in July 1974, where I submitted to them my first ideas for a treatise on structural optimization: It should cover the whole domain from basic theory to practical applications, and deal with various materials, various types of structures, various functions required of the structures, and various types of cost . . Obviously, this was to be a team effort, to total three or four volumes, to be written in a balanced manner as textbooks and handbooks. Nothing similar existed at that time, and, indeed, nothing has been published to date. Professor Prager was immedi ately in favor of such a project. He agreed to write a first part on optimality criteria with me and to help me in the general organization of the series. Since Professor Sacchi was willing to write the text on variational methods, it remained to find authors for parts on the mathematical programming approach to structural optimization (and, more generally, on numerical methods) and on practical optimal design procedures in metal and concrete.
Download or read book Optimum Design of Simple Structures Using an Optimality Criterion written by Kat Chung Choy and published by . This book was released on 1973 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Michell Structures written by Tomasz Lewiński and published by Springer. This book was released on 2018-09-27 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book covers the theory of Michell structures being the lightest and fully stressed systems of bars, designed within a given domain, possibly within the whole space, transmitting a given load towards a given support. Discovered already in 1904 by A.G.M. Michell, the structures named after him have attracted constant attention due to their peculiar feature of disclosing the optimal streams of stresses equilibrating a given load and thus determining the optimal layout of bars. The optimal layouts emerge from among all possible structural topologies, thus constituting unique designs being simultaneously light and stiff. The optimal structures turn out to be embedded in optimal vector fields covering the whole feasible domain. Key features include: a variationally consistent theory of bar systems, thin plates in bending and membrane shells; recapitulation of the theory of optimum design of trusses of minimum weight or of minimal compliance; the basis of 2D Michell theory for a single load case; kinematic and static approaches; 2D benchmark constructions including Hemp’s structures and optimal cantilevers; L-shape domain problems, three forces problem in 2D, bridge problems; revisiting the old - and delivering new - 3D benchmark solutions; extension to multiple load conditions; Prager-Rozvany grillages; the theory of funiculars and archgrids; the methods of optimum design of shape and material inspired by the theory of Michell structures, industrial applications. The book can be useful for graduate students, professional engineers and researchers specializing in the Optimum Design and in Topology Optimization in general.
Download or read book Optimization of Large Structural Systems written by George I. N. Rozvany and published by Springer Science & Business Media. This book was released on 2013-11-21 with total page 1201 pages. Available in PDF, EPUB and Kindle. Book excerpt: G.I.N. Rozvany ASI Director, Professor of Structural Design, FB 10, Essen University, Essen, Germany Structural optimization deals with the optimal design of all systems that consist, at least partially, of solids and are subject to stresses and deformations. This inte grated discipline plays an increasingly important role in all branches of technology, including aerospace, structural, mechanical, civil and chemical engineering as well as energy generation and building technology. In fact, the design of most man made objects, ranging from space-ships and long-span bridges to tennis rackets and artificial organs, can be improved considerably if human intuition is enhanced by means of computer-aided, systematic decisions. In analysing highly complex structural systems in practice, discretization is un avoidable because closed-form analytical solutions are only available for relatively simple, idealized problems. To keep discretization errors to a minimum, it is de sirable to use a relatively large number of elements. Modern computer technology enables us to analyse systems with many thousand degrees of freedom. In the optimization of structural systems, however, most currently available methods are restricted to at most a few hundred variables or a few hundred active constraints.
Download or read book Optimization in Civil Environmental Engineering written by Zong Woo Geem and published by Archives contemporaines. This book was released on 2012 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1973 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt:
