Optimal Structural Design under Stability Constraints

A total of over 70 books has been devoted to structural optimization as yet, but none of them has treated stability constraints in a sufficiently broad and comprehensive manner. The purpose of the present book is to fill this gap.

Author: Antoni Gajewski

Publisher: Springer Science & Business Media

ISBN: 9400927541

Category: Science

Page: 470

View: 203

The first optimal design problem for an elastic column subject to buckling was formulated by Lagrange over 200 years ago. However, rapid development of structural optimization under stability constraints occurred only in the last twenty years. In numerous optimal structural design problems the stability phenomenon becomes one of the most important factors, particularly for slender and thin-walled elements of aerospace structures, ships, precision machines, tall buildings etc. In engineering practice stability constraints appear more often than it might be expected; even when designing a simple beam of constant width and variable depth, the width - if regarded as a design variable - is finally determined by a stability constraint (lateral stability). Mathematically, optimal structural design under stability constraints usually leads to optimization with respect to eigenvalues, but some cases fall even beyond this type of problems. A total of over 70 books has been devoted to structural optimization as yet, but none of them has treated stability constraints in a sufficiently broad and comprehensive manner. The purpose of the present book is to fill this gap. The contents include a discussion of the basic structural stability and structural optimization problems and the pertinent solution methods, followed by a systematic review of solutions obtained for columns, arches, bar systems, plates, shells and thin-walled bars. A unified approach based on Pontryagin's maximum principle is employed inasmuch as possible, at least to problems of columns, arches and plates. Parametric optimization is discussed as well.

Structural Optimization Under Stability and Vibration Constraints

Prager, W.: Optimality criteria in structural design, Proc. Nat. ... Save, H.A.: A general criterion for optimal structural design, J. Optimiz. ... Eajewski, A. and M. Zyczkowski: design under stability constraints, Dordrecht 1988.

Author: M. Zyczkowski

Publisher: Springer

ISBN: 3709129699

Category: Technology & Engineering

Page: 329

View: 355

Optimal design of structures leads, as a rule, to slender and thin-walled shapes of the elements, and such elements are subject to the loss of stability. Hence the constraints of structural optimization usually include stability constraints, expressed by some eigenvalues. Optimal design under vibration constraints belongs also to optimization with respect to eigenvalues. The present volume gives a short introduction to structural optimization and then pays particular attention to multimodal optimization under stability and vibration constraints, both in elastic and inelastic range. One part is devoted to thin-walled bars optimized for interactive buckling with imperfections taken into account. The volume is of interest both to researchers and design engineers: it covers the most recent results of multimodal and interactive optimization, allowing for inelastic behaviour of structures, and the constraints discussed appear in almost all problems of engineering design.

Elements of Structural Optimization

Springer-Verlag, 1975, pp. 82–103. [32] Gajewski, A., and Zyczkowski, M., Optimal Structural Design under Stability Constraints, Kluwer Academic Publishers, 1988. [33] Niordson, F.I., “On the Optimal Design of a Vibrating Beam,” Quart.

Author: Raphael T. Haftka

Publisher: Springer Science & Business Media

ISBN: 9401125503

Category: Technology & Engineering

Page: 481

View: 548

The field of structural optimization is still a relatively new field undergoing rapid changes in methods and focus. Until recently there was a severe imbalance between the enormous amount of literature on the subject, and the paucity of applications to practical design problems. This imbalance is being gradually redressed. There is still no shortage of new publications, but there are also exciting applications of the methods of structural optimizations in the automotive, aerospace, civil engineering, machine design and other engineering fields. As a result of the growing pace of applications, research into structural optimization methods is increasingly driven by real-life problems. t-.Jost engineers who design structures employ complex general-purpose software packages for structural analysis. Often they do not have any access to the source program, and even more frequently they have only scant knowledge of the details of the structural analysis algorithms used in this software packages. Therefore the major challenge faced by researchers in structural optimization is to develop methods that are suitable for use with such software packages. Another major challenge is the high computational cost associated with the analysis of many complex real-life problems. In many cases the engineer who has the task of designing a structure cannot afford to analyze it more than a handful of times.

Large Scale Optimization with Applications

Part I: Optimization in Inverse Problems and Design Lorenz T. Biegler, Andrew R. Conn, Thomas F. Coleman, Fadil N. Santosa. 6. Conclusions . Structural ... Optimal structural design under stability constraints . In J. M. T. Thompson and ...

Author: Lorenz T. Biegler

Publisher: Springer Science & Business Media

ISBN: 9780387982861

Category: Business & Economics

Page: 204

View: 551

With contributions by specialists in optimization and practitioners in the fields of aerospace engineering, chemical engineering, and fluid and solid mechanics, the major themes include an assessment of the state of the art in optimization algorithms as well as challenging applications in design and control, in the areas of process engineering and systems with partial differential equation models.

Structural Design via Optimality Criteria

QIAN L., Structural Optimization Research in China. Eng. Opt. 6, 4, 185-192. ZYCZKOWSKI, M. & GAJEWSKI, A., Optimal Structural Design under Stability Constraints. In: THOMPSON and HUNT (Eds.), Chapter 19, pp. 299-332.

Author: George I. N. Rozvany

Publisher: Springer Science & Business Media

ISBN: 9400911610

Category: Technology & Engineering

Page: 490

View: 514

"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.

Applied Mechanics Reviews

Shield , R. T. , and Prager , W. , Optimal structural design for given deflection ( in English ) , Zeitschrift fur ... weight design with Mathematik und Physik 21 , 4 , 513-523 ( 1970 ) . stability constraint , Journal of the Structural ...




Category: Mechanics, Applied


View: 922

Recent Advances in Optimal Structural Design

On structural optimization with aeroelasticity constraints Structural Optimisation , v 8 n 1 1994. p 16-23 . 1684 Rivin , Eugene I. Structural optimization of cantilever mechanical elements , Journal of Vibration & Acoustics ...

Author: Scott A. Burns

Publisher: ASCE Publications

ISBN: 9780784475249

Category: Technology & Engineering

Page: 312

View: 935

Sponsored by the Technical Committee on Structural Design of the Technical Administrative Committee on Analysis and Computation of the Technical Activities Division of the Structural Engineering Institute of ASCE. This report documents the dramatic new developments in the field of structural optimization over the last two decades. Changes in both computational techniques and applications can be seen by developments in computational methods and solution algorithms, the role of optimization during the various stages of structural design, and the stochastic nature of design in relation to structural optimization. Topics include: Ømethods for discrete variable structural optimization; Ødecomposition methods in structural optimization; Østate of the art on the use of genetic algorithms in design of steel structures; Øconceptual design optimization of engineering structures; Øtopology and geometry optimization of trusses and frames; Øevolutionary structural optimization; Ødesign and optimization of semi-rigid framed structures; Øoptimized performance-based design for buildings; Ømulti-objective optimum design of seismic-resistant structures; and Øreliability- and cost-oriented optimal bridge maintenance planning. The book concludes with an extensive bibliography of journal papers on structural optimization published between 1987 and 1999.

Engineering Optimization in Design Processes

To check the validity of our assumption, we computed a posteri ori the critical loads associated with in-plane ... Gajewski , A. ; Zyczkowski, M. , C 1988) : Optimal structural design under stability constraints, Dordrecht 2 Boston.

Author: Hans A. Eschenauer

Publisher: Springer Science & Business Media

ISBN: 3642843972

Category: Technology & Engineering

Page: 355

View: 102

These proceedings contain the texts of 37 contributions presented at the International Conference on Engineering Optimization in an Industrial Environment, which took place on 3 - 4 September 1990 at the Karlsruhe Nuclear Hesearch Center, I~H Germany. The presentations consisted of oral and poster contributions arranged in five sessions: • Shape and layout optimization • Structural optimization with advanced materials • Optimal designs with special structural and material beha viour • Sensitivity analysis - Programme systems • Optimization with stability constraints - Special problems The editors wish to express their appreciation to all authors and invited speakers for their in teresting contributions. The proceedings cover a wide range of topics in structural optimization representing the present state of the art in the fields of research and in the industrial environment as well. The editors hope that this book will also contribute towards new ideas and concepts in a world of ever decreasing natural resources and ever increasing demands for lighter and yet stronger and safer technical components. I"inally, the editors wish to thank all colleagues who helped in the organisation of the conference, especially Mrs. E. Schroder anq Dr. K.llethge, as well as Mr. A. von lIagen and Mrs. E. Haufelder, Springer Publishing Company, Heidelberg for the good cooperation and help in the publication of these proceedings.

Structural Optimization

Optimization in Structural Design, Warsaw 1973, Springer-Verlag 1975, pp. 168-180. [8] Bogacz R., Irretier H. and Mahrenholtz O., 'Optimal Design of Structures under Non-Conservative Forces with Stability Constraints'.

Author: George I. N. Rozvany

Publisher: Springer Science & Business Media

ISBN: 940091413X

Category: Technology & Engineering

Page: 424

View: 135

Proceedings of the IUTAM Symposium on Structural Optimization, Melbourne, Australia, February 9-13, 1988

Discretization Methods and Structural Optimization Procedures and Applications

Optimization in Structural Design. Warsaw 1973, SpringerWerlag 1975, pp. 168-180. (4) R. Bogacz. H. Irretier and O. Mahrenholtz, Optimal Design of Structures under Non-Conservative Forces with Stability Constraints'.

Author: Hans A. Eschenauer

Publisher: Springer Science & Business Media

ISBN: 3642837077

Category: Technology & Engineering

Page: 360

View: 162

In recent years, the Finite Element Methods FEM were more and more employed in development and design departments as very fast working tools in order to determine stresses, deformations, eigenfrequencies etc. for all kinds of constructions under complex loading conditions. Meanwhile. very effective software systems have been developed by various research teams although some mathematical problems (e. g. convergence) have not been solved satisfac torily yet. In order to make further advances and to find a common language between mathe maticians and mechanicians the "Society for Applied Mathematics and Mechanics" (GAMM) agreed on the foundation of a special Committee: "Discretization Methods in Solid Mechanics" focussing on the following problems: - Structuring of various methods (displacement functions, hybrid and mixed approaches, etc. >, - Survey of approach functions (Lagrange-/Hermite-polynominals, Spline-functions), - Description of singularities, - Convergence and stability, - Practical and theoretical optimality to all mentioned issues (single and interacting). One of the basic aims of the GAMM-Committee is the interdisciplinary cooperation between mechanicians, mathematicians, and users which shall be intensified. Thus, on September 22, 1985 the committee decided to hold a seminar on "Structural Optimization" in order to allow an exchange of experiences and thoughts between the experts of finite element methods and those of structural optimization. A GAMM-seminar entitled "Discretization Methods and Structural Optimization - Procedures and Applications" was hold on October 5-7, 1988 at the Unversity of Siegen.