Our topic is irreversible or plastic deformation of structural elements composed of relatively thin ductile materials. These deformations are commonly used in sheet metal forming operations to produce lightweight parts of any particular shape. In another context, this type of plastic deformation is described as impact damage in the case of structural components involved in collision. Here we are concerned with mechanics of both static and dynamic deformation processes. The purpose is to use typical material properties and structural characteristics to calculate the deformation for certain types of load; in particular to find the final deflection and shape of the deformed structure and to illustrate how the development of this final shape depends on the constitutive model used to represent the material behavior. The major issue to be addressed is which structural and constitutive properties are important for calculating response to either static or brief but intense dynamic loads. Furthermore, how do the results of various constitutive models compare with observed behavior.

This volume is the first to give the mathematical background and a comprehensive survey of the old and new summation formulae resulting in an approximate value of the critical load factor of a complex problem by means of the critical load factors of subproblems by addition. The theorems and formulae are richly illustrated by examples in structural engineering.

This text explores how academics face up to radical changes in the learning environment. With the implementation of new technologies to support teaching and learning there is a need for more strategic approaches to teaching and learning. At the same time there are requirements to respond to a much more diverse student body and therfore a greater need for staff developments to help the teachers and the learners to cope with the new environments for learning.

The Student Book and ActiveBook has clearly laid out pages with a range of supportive features to aid learning and teaching: Getting to know your unit sections ensure learners understand the grading criteria and unit requirements Getting ready for Assessment sections focus on preparation for external assessment with guidance for learners on what to expect. Hints and tips will help them prepare for assessment and sample answers are provided for a range of question types including, short and long answer questions, all with a supporting commentary. Learners can also prepare for internal assessment using this feature. A case study of a learner completing the internal assessment for that unit covering 'How I got started', 'How I brought it all together' and 'What I got from the experience'. Pause Point features provide opportunities for learners to self-evaluate their learning at regular intervals. Each Pause Point point feature gives learners a Hint or Extend option to either revisit and reinforce the topic or encourage independent research or further study skills. Case Study and Theory in Practice features enable development of problem-solving skills and place the theory into real life situations learners could encounter. Assessment Activity/Practice features provide scaffolded assessment practice activities that help prepare learners for formative assessment. Within each assessment practice activity, a Plan, Do and Review section encourages supports learners' formative assessment by to making sure they fully understand what they are being asked to do, what their goals are and how to evaluate the task and consider how they could improve. Dedicated Think Future pages provide case studies from the industry, with a focus on aspects of skills development that can be put into practice in a real work environment and further study.

Base isolation, passive energy dissipation and active control represent three innovative technologies for protection of structures under environmental loads. Increasingly, they are being applied to the design of new structures or to the retrofit of existing structures against wind, earthquakes and other external loads. This book, with contributions from leading researchers from Japan, Europe, and the United States, presents a balanced view of current research and world-wide development in this exciting and fast expanding field. Basic principles as well as practical design and implementational issues associated with the application of base isolation systems and passive and active control devices to civil engineering structures are carefully addressed. Examples of structural applications are presented and extensively discussed.

The chapters of this book were written by structural engineers. The approach, therefore, is not aiming toward a scientific modelling of the response but to the definition of engineering procedures for detecting and avoiding undesired phenomena. In this sense chaotic and stochastic behaviour can be tackled in a similar manner. This aspect is illustrated in Chapter 1. Chapters 2 and 3 are entirely devoted to Stochastic Dynamics and cover single-degree-of-freedom systems and impact problems, respectively. Chapter 4 provides details on the numerical tools necessary for evaluating the main indexes useful for the classification of the motion and for estimating the response probability density function. Chapter 5 gives an overview of random vibration methods for linear and nonlinear multi-degree-of-freedom systems. The randomness of the material characteristics and the relevant stochastic models ar considered in Chapter 6. Chapter 7, eventually, deals with large engineering sytems under stochastic excitation and allows for the stochastic nature of the mechanical and geometrical properties.

Slender structures, such as towers, masis, high-rise buildings and bridges, are especially prone to wind excited vibrations. The lectures show how the susceptibility of a structure to wind excited vibrations can be assessed in early stages of design, and what measures are effective for control or avoidance of vibrations. The book will be a help for all dealing with dynamic response of structures.

A synthetic presentation of the theory of yield design is illustrated by examples such as the stability analysis of reinforced soil structures and the resistance of long fiber reinforced composite materials. The classical limit analysis theory when standard elastic perfectly plastic behaviour can be assumed yields a more precise assessment of the global bearing capacities of structures and makes optimal limit design possible. Structural optimal design is also studied with respect to eigenvalues as well as Structural Topology and Design Optimization.

This book was developed while teaching a graduate course at several universities in the United States. Europe and Israel. during the last two decades. The purpose of the book is to introduce the fundamentals and applications of optimum structural design. Much work has been done in this area recently and many studies have been published. The book is an attempt to collect together selected topics of this literature and to present them in a unified approach. It meets the need for an introductory text covering the basic concepts of modem structural optimization. A previous book by the author on this subject ("Optimum Structural Design." published by McGraw-Hill New York in 1981 and by Maruzen Tokyo in 1983). has been used extensively as a text in many universities throughout the world. The present book reflects the rapid progress and recent developments in this area. A major difficulty in studying structural optimization is that integration of concepts used in several areas. such as structural analysis. numerical optimization and engineering design. is necessary in order to solve a specific problem. To facilitate the study of these topics. the book discusses in detail alternative problem formulations. the fundamentals of different optimization methods and various considerations related to structural design. The advantages and the limitations of the presented approaches are illustrated by numerous examples.

Design of Welded Steel Structures: Principles and Practice provides a solid foundation of theoretical and practical knowledge necessary for the design of welded steel structures. The book begins by explaining the basics of arc welding, describing the salient features of modern arc welding processes as well as the types and characteristics of welded joints, their common defects, and recommended remedial measures. The text then: Addresses the analysis and design of welded structures Explores the design of joints in respect to common welded steel structures Identifies the cost factors involved in welded steelwork Design of Welded Steel Structures: Principles and Practice draws not only from the author's own experience, but also from the vast pool of research conducted by distinguished engineers around the globe. Detailed bibliographies are included at the end of each chapter.

This volume strives to give complete information about the main aspect of the stability behaviour of steel structures and their members. In following this objective, the volume presents a complete scientific background (profiting from the fact that the authors of the individual parts of the publication have personally been very active in the corresponding field of research for an extended period of time now), but also establishes recommendations, procedures and formulae for practical design. The significance of the volume may be seen in its challenging current concepts of stability analysis, encouraging progress in the field and thereby establishing an advanced basis for more reliable and economical design.

State-of-the-art nonlinear computational analysis of shells, nonlinearities due to large deformations and nonlinear material behavior, alternative shell element formulations, algorithms and implementational aspects, composite and sandwich shells, local and global instabilities, optimization of shell structures and concepts of shape finding methods of free from shells. Furthermore, algorithms for the treatment of the nonlinear stability behavior of shell structures (including bifurcation and snap-through buckling) are presented in the book.

This book provides an up-to-date survey of durability issues, with a particular focus on specification and design, and how to achieve durability in actual concrete construction. It is aimed at the practising engineer, but is also a valuable resource for graduate-level programs in universities. Along with background to current philosophies it gathers together in one useful reference a summary of current knowledge on concrete durability, includes information on modern concrete materials, and shows how these materials can be combined to produce durable concrete. The approach is consistent with the increasing focus on sustainability that is being addressed by the concrete industry, with the current emphasis on 'design for durability'.

This proceedings volume contains 38 papers presented at the 4th Working Conference on "Rel iability* and Optimization of Structural Systems", held at the Technical University of Munich, Germany, September 11- 13, 1991. The Working Conference was organised by the IFIP (Interna tional Federation for Information Processing) Working Group 7.5 of Technical Committee 7 and was the fourth in a series, following similar conferences held at the University of Aalborg, Den mark, May 1987, at the Imperial College, London, UK, September 1988 and at the University of California, Berkeley, California, USA, March 1990. The Working Conference was attended by 54 participants from 16 countries. The objectives of Working Group 7.5 are: * to promote modern structural systems optimization and reliability theory, * to advance international cooperation in the field of structural system optimization and reliability theory, * to stimulate research, development and application of structural system optimization and reli ability theory, * to further the dissemination and exchange of information on reliability and optimization of structural systems * to encourage education in structural system optimization and reliability theory. At present the members of the Working Group are: A. H.-S. Ang, U.S.A. M. Grimmelt, FRG G. A ugwti, Italy N. C. Lind, Canada M. J. Baker, UK H. O. Mad&en, Denmark P. Bjerager, Norway R. E. Melcher~, Australia C. A. Cornell, U.S.A. F. Mo~e~, U.S.A.

Shape and layout optimization represent some of the most useful but also most difficult classes of problems in structural design, which have been investigated in detail only during the last few years. "Shape optimization" is concerned with the optimal shape of boundaries of continua or of interfaces between two materials in composites. "Layout" "optimization" deals with the simultaneous optimization of the topology, geometry and cross-sectional sizes of structural systems. In spite of its complextiy, layout optimization is a very rewarding task, because it results in much greater savings than the optimization of cross-sectional sizes only. Because of their important role in shape and layout optimization, the book also covers in detail new "optimality " "criteria methods," which are capable of handling many thousand design variables and active design contraints. Shape and layout optimization is becoming an indispensable tool in the design of aeroplanes, space structures, cars, ships, building and civil engineering structures, power stations, chemical plants, artificial organs, sporting equipment, and all other solid systems where stresses and deformations play an important role.

Structural Reliability Analysis and Prediction, Third Edition is a textbook which addresses the important issue of predicting the safety of structures at the design stage and also the safety of existing, perhaps deteriorating structures. Attention is focused on the development and definition of limit states such as serviceability and ultimate strength, the definition of failure and the various models which might be used to describe strength and loading. This book emphasises concepts and applications, built up from basic principles and avoids undue mathematical rigour. It presents an accessible and unified account of the theory and techniques for the analysis of the reliability of engineering structures using probability theory. This new edition has been updated to cover new developments and applications and a new chapter is included which covers structural optimization in the context of reliability analysis. New examples and end of chapter problems are also now included.

This volume deals with the most modern and topical problems of bridge design. The topics presented allow to tackle both theoretical-analytical as well as technical-constructive aspects of the design problem, pointing out how in the case of bridges, specifically for long span bridges, the two aspects are absolutely inseparable. In modern bridges, reasons of technical and economic feasibility oblige an extreme parceling of the construction process, with the consequent need to revise, with respect to the past, both design concepts as well as the theoretical apparatus of analysis that governs it. All this can clearly be derived from reading the present volume, in which the different contributions stress theoretical and technical questions of particular interest and topicality, without claiming to approach them systematically, but offering clear procedural rules and trend indications. With reference to the theoretical approach, some of particular importance are reviewed, such as the possibility of using limit analysis, the simplification of the design process for bridges, durability, and computer aided design. For what concerns the bridge typologies and the corresponding constructive problems, the emphasis is mostly on the ones still in an evolutionary phase, that is long span suspended/stayed bridges and cantilever built bridges with prefabricated segments.

Virtual distortions are incompatible deIormations imposed on structures (e. g. , by nonhomogeneous heating or by local imperIections) causing a compatible state OI deIormation (initial deformations) and a selI-equilibrated state OI stress (initial stresses). The theory OI virtual distortions provides an eIIicient tool which can be used to treat many problems that diIIer Irom the physical point OI view. Thermal stresses, material deIects, residual stresses in plasticity are examples OI problems that can be analysed emploing the virtual distortions approach, where the temperature Iield, dislocations and plastic distortions (permanent plastic deIormations) are described by virtual distortions. The presented approach allows the development OI eIIicient computational methods Ior numerical analysis OI such problems. States OI compatible deIormations and selI-equi1 ibrated stresses caused by virtual distortions in homogeneous and compound (biphase) bodies are analysed in the Iirst part OI the book. The results OI these considerations are explored in the next two chapters. The Iormulation OI the approach discussed in Chapter 1 and based on continuum mechanics was presented previously in the papers [5,17] while its application to the analysis OI skeletal structures was discussed in [47].

This proceedings volume contains 33 papers presented at the 3rd Working Conference on "Rel- iability and Optimization of Structural Systems", held at the University of California, Berkeley, California, USA, March 26 -28, 1990. The Working Conference was organised by the IFIP (Inter- national Federation for Information Processing) Working Group 7.5 of Technical Committee 7 and was the third in a series, following similar conferences held at the University of Aalborg, Denmark, May 1987 and at the Imperial College, London, UK, September 1988. The Working Conference was attended by 48 participants from 12 countries. The objectives of Working Group 7.5 are: * to promote modern structural systems optimization and reliability theory, * to advance international cooperation in the field of structural system optimization and reliability theory, * to stimulate research, development and application of structural system optimization and reli- ability theory, * to further the dissemination and exchange of information on reliability and optimization of structural systems * to encourage education in structural system optimization and reliability theory. At present the members of the Working Group are: A. H.-S. Ang, U.S.A. G. A ugusti, Italy M. J. Baker, United Kingdom P. Bjerager, Norway R. B. Corotis, U.S.A. C. A. Cornell, U.S.A. M. Grigoriu, U.S.A. A. Der Kiureghian, U.S.A. O. Ditlevsen, Denmark D. M. Frangopol, U.S.A. S. Garribba, Italy H. Furuta, Japan M. R. Gorman, U.S.A. M. Grimmelt, Germany, F. R.

This book presents a method which is capable of evaluating the deformation characteristics of thin shell structures A free vibration analysis is chosen as a convenient means of studying the displacement behaviour of the shell, enabling it to deform naturally without imposing any particular loading conditions. The strain-displacement equations for thin shells of arbitrary geometry are developed. These relationships are expressed in general curvilinear coordinates and are formulated entirely in the framework of tensor calculus. The resulting theory is not restricted to shell structures characterized by any particular geometric form, loading or boundary conditions. The complete displacement and strain equations developed by Flugge are approximated by the curvilinear finite difference method and are applied to computing the natural frequencies and mode shapes of general thin shells. This approach enables both the displacement components and geometric properties of the shell to be approximated numerically and accurately. The selection of an appropriate displacement field to approximate the deformation of the shell within each finite difference mesh is discussed in detail. In addition, comparisons are made between the use of second and third-order finite difference interpolation meshes.

1. 1 Introduction As offshore oil production moves into deeper water, compliant structural systems are becoming increasingly important. Examples of this type of structure are tension leg platfonns (TLP's), guyed tower platfonns, compliant tower platfonns, and floating production systems. The common feature of these systems, which distinguishes them from conventional jacket platfonns, is that dynamic amplification is minimized by designing the surge and sway natural frequencies to be lower than the predominant frequencies of the wave spectrum. Conventional jacket platfonns, on the other hand, are designed to have high stiffness so that the natural frequencies are higher than the wave frequencies. At deeper water depths, however, it becomes uneconomical to build a platfonn with high enough stiffness. Thus, the switch is made to the other side of the wave spectrum. The low natural frequency of a compliant platfonn is achieved by designing systems which inherently have low stiffness. Consequently, the maximum horizontal excursions of these systems can be quite large. The low natural frequency characteristic of compliant systems creates new analytical challenges for engineers. This is because geometric stiffness and hydrodynamic force nonlinearities can cause significant resonance responses in the surge and sway modes, even though the natural frequencies of these modes are outside the wave spectrum frequencies. High frequency resonance responses in other modes, such as the pitch mode of a TLP, are also possible.

Following the popularity of the previous edition, Shallow Foundations: Bearing Capacity and Settlement, Third Edition, covers all the latest developments and approaches to shallow foundation engineering. In response to the high demand, it provides updated data and revised theories on the ultimate and allowable bearing capacities of shallow foundations. Additionally, it features the most recent developments regarding eccentric and inclined loading, the use of stone columns, settlement computations, and more. Example cases have been provided throughout each chapter to illustrate the theories presented.

Construction time constraints are partly responsible for the increasingly prevalent use of structural steel. The need for swift completed framework and fabrication is of paramount importance. This extensive manual looks at the various aspects of steel construction. It covers the full scope of structural steelwork detailing, including fundamentals, draughting practice and conventions, conventional methods of detailing components, full scale constructed facilities and computer aided practices. A number of codes have also been included for those engineers who wish to carryout in-depth study of practices where jobs are in progress.

Civil engineering structures tend to be fabricated from materials that respond elastically at normal levels of loading. Most such materials, however, would exhibit a marked and ductile inelasticity if the structure were overloaded by accident or by some improbable but naturally occuring phenomeon. Indeed, the very presence of such ductility constitutes an important safety provision for large-scale constructions where human life is at risk. In the comprehensive evaluation of safety in structural design, it is therefore unrealistic not to consider the effects of ductility. This book sets out to show that the bringing together of the theory and methods of mathematical programming with the mathematical theory of plasticity furnishes a model which has a unifying theoretical nature and is entirely representative of observed structural behaviour. The contents of the book provide a review of the relevant aspects of mathematical programming and plasticity theory, together with a detailed presentation of the most interesting and potentially useful applications in both framed and continuum structures: ultimate strength and elastoplastic deformability; shakedown and practical upper bounds on deformation measures; evolutive dynamic response; large displacements and instability; stochastic and fuzzy programming for representing uncertainty in ultimate strength calculations. Besides providing a ready fund of computational algorithms, mathematical programming invests applications in mechanics with a refined mathematical formalism, rich in fundamental theorems, which often gives addi- tional insight into known results and occasionally lead to new ones. In addition to its obvious practical utility, the educational value of the material thoroughly befits a university discipline.

Structural safety of industrial systems and components raises a steadily growing public, scientific and engineering interest, and causes permanent development of methods and techniques used for its assessment. In addition to the well established engineering methods, applied in the field, several new methods and tools have emerged recently. Among them, the most novel ones are probably those related to expert system applica tions, appearing as an important possible improvement of the current engineering practice. The issue has been addressed by the international course EXPERT SYSTEMS IN STRUCTURAL SAFETY ASSESSMENT organized by MPA Stuttgart and JRC Ispra (Stuttgart, October 2-4, 1989), and the proceedings of the course are contained in this volume of the Lecture Notes ill Engineering. The contributions (invited lectures) tackle the issues usually confronting developers and users of expert systems applied in structural engineering, i.e. in structural safety and integrity assessment. Both the book and the course are a combination of a tutorial and of presentation of the current achievements in the field. Starting from the basic elements of expert systems (knowledge based systems), the book should "guide" the reader up to the applications in various particular sub-domains.