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The first part of this book covers the general theory of structural dynamics, in a calculous format as well as a finite element formulation. Secondly, it contains methods of eigenvalue calculations of civil engineering structural systems. And third, it contains a major part covering dynamic displacement response calculations as induced by earthquake, turbulent wind, vortex shedding and moving vehicles, enabling the designer to evaluate structural safety from the effects of fluctuating internal forces.The general theory contains comprehensive development of the principle of virtual displacements, as well as the Galerkin solution to eigenvalue problems. A separate chapter has been dedicated to the suspension bridge. The theory of single or multiple tuned mass dampers is included, a theory not presented elsewhere.The book contains a chapter covering the theory of structural damping, as well as comprehensive data of the structural damping properties that are necessary forany dynamic response calculation. The book is intended for students as well as practising engineers. It contains numerous relevant examples, covering numerical solutions that are well suited for computer programming.

This book discusses the conceptual theory of structural dynamics, using simplified methods and clear, concise explanations. It illustrates all the hypotheses in a simple and effective way and describes in detail the derivation of all related formulations. Further, comprehensive step-by-step explanations combined with conceptual derivations, drawings and figures allow readers to grasp all the analytical formulations related to the dynamics of structures. Covering free and forced vibrations of single- and multi-degree of freedom systems represented as structure, subjected to dynamic load, the book also explores the most common types of dynamic loads applicable to structures, such as harmonic loads, impact loads and earthquakes, presenting relevant details, derivations and effective problems to explain the concept for various conditions. In addition, each chapter provides examples at different levels to help students, researchers and engineers gain a better understanding of the topics better, and includes numerous real-world problems to familiarize readers with the challenges related to structural engineering.

This book develops a uniform accurate method which is capable of dealing with vibrations of laminated beams, plates and shells with arbitrary boundary conditions including classical boundaries, elastic supports and their combinations. It also provides numerous solutions for various configurations including various boundary conditions, laminated schemes, geometry and material parameters, which fill certain gaps in this area of reach and may serve as benchmark solutions for the readers.For each case, corresponding fundamental equations in the framework of classical and shear deformation theory are developed. Following the fundamental equations, numerous free vibration results are presented for various configurations including different boundary conditions, laminated sequences and geometry and material properties. The proposed method and corresponding formulations can be readily extended to static analysis.

Mechanical Vibrations: Theory and Application to Structural Dynamics, Third Edition is a comprehensively updated new edition of the popular textbook. It presents the theory of vibrations in the context of structural analysis and covers applications in mechanical and aerospace engineering. Key features include: A systematic approach to dynamic reduction and substructuring, based on duality between mechanical and admittance concepts An introduction to experimental modal analysis and identification methods An improved, more physical presentation of wave propagation phenomena A comprehensive presentation of current practice for solving large eigenproblems, focusing on the efficient linear solution of large, sparse and possibly singular systems A deeply revised description of time integration schemes, providing framework for the rigorous accuracy/stability analysis of now widely used algorithms such as HHT and Generalized-α Solved exercises and end of chapter homework problems A companion website hosting supplementary material

The aim of the present book is to address practical aspects of nonlinear vibration analysis. It presents cases rarely discussed in the existing literature on vibration - such as rotor dynamics, and torsional vibration of engines - which are problems of considerable interest for engineering researchers and practical engineers. The book can be used not only as a reference but also as material for graduate students at Engineering departments, as it contains problems and solutions for each chapter.

This text addresses the modeling of vibrating systems with the perspective of finding the model of minimum complexity which accounts for the physics of the phenomena at play. The first half of the book (Ch.1-6) deals with the dynamics of discrete and continuous mechanical systems; the classical approach emphasizes the use of Lagrange's equations. The second half of the book (Ch.7-12) deals with more advanced topics, rarely encountered in the existing literature: seismic excitation, random vibration (including fatigue), rotor dynamics, vibration isolation and dynamic vibration absorbers; the final chapter is an introduction to active control of vibrations. The first part of this text may be used as a one semester course for 3rd year students in Mechanical, Aerospace or Civil Engineering. The second part of the text is intended for graduate classes. A set of problems is provided at the end of every chapter. The author has a 35 years experience in various aspects of Structural dynamics, both in industry (nuclear and aerospace) and in academia; he was one of the pioneers in the field of active structures. He is the author of several books on random vibration, active structures and structural control.

This volume contains eighteen selected papers presented at the Second International Conference on Stochastic Structural Dynamics, which are related to new theoretical developments in the field. This and a companion volume, related to new practical applications, constitute the proceedings of the conference, and reflect the state of the art of the rapidly developing subject. The conference was held in Boca Raton, Florida during May 9-11, 1990 hosted by the Center for Applied Stochastics Research of Florida Atlantic University. A total of 20 technical sessions were organized, and attended by eighty participants from 12 countries. Special emphases of the conference were placed on two areas: applications to earthquake engineering and stochastic stability of nonlinear systems. Two sessions were dedicated to the memory of late Professor Frank Kozin, one of the founders and most active contributors to the stochastic stability theory. We are indebted to the National Center for Earthquake Engineering Research (NCEER) for financial support. Most credit belongs to each of the authors whose contributions were the very basis for the undoubted success of the conference. We are grateful to the reviewers who carefully refereed the contributions for these two volumes. Our special thanks are due to Mrs. Christine Mikulski, who carried out all the necessary secretarial tasks associated with the conference with dedication.

From time to time the International Journal of Fracture has presented matters thought to be of special interest to its readers. In previous special issues (December 1980 and April 1981), Dr H.W. Liu as Guest Editor presented a series of review papers dealing with fatigue processes and characteristics in metals and non-metals. Continuing this policy, which is consistent with our stated objectives, a second review dealing with time depen­ dence in the fracture process, including the effect of material inertia but essentially excluding very strong shock effects in solids, has been assembled under the generic term'dynamic fracture'. We hope that the ensuing state-of-the-art review will yield an instructive and timely product which readers will find useful. To assist us in presenting this subject, we have prevailed upon a well-known worker in dynamic fracture, Dr W.G. Knauss, Professor of Aeronautics and Applied Mechanics, California Institute of Technology to act as Guest Editor for this special double issue. On behalf of the editors and publisher, I wish to express our indebtedness to Professor Knauss and his invited authors for undertaking this special effort.

Dynamic instability or dynamic buckling as applied to structures is a term that has been used to describe many classes of problems and many physical phenomena. It is not surprising, then, that the term finds several uses and interpretations among structural mechanicians. Problems of parametric resonance, follower-force, whirling of rotating shafts, fluid-solid interaction, general response of structures to dynamic loads, and several others are all classified under dynamic instability. Many analytical and experimental studies of such problems can be found in several books as either specialized topics or the main theme. Two such classes, parametric resonance and stability of nonconservative systems under static loads (follower-force problems), form the main theme of two books by V. V. Bolotin, which have been translated from Russian. Moreover, treatment of aero elastic instabilities can be found in several textbooks. Finally, analytical and experimental studies of structural elements and systems subjected to intense loads (of very short duration) are the focus of the recent monograph by Lindberg and Florence. The first chapter attempts to classify the various'dynamic instability'phenomena by taking into consideration the nature of the cause, the character of the response, and the history of the problem. Moreover, the various concepts and methodologies as developed and used by the various investigators for estimating critical conditions for suddenly loaded elastic systems are fully described. Chapter 2 demonstrates the concepts and criteria for dynamic stability through simple mechanical models with one and two degrees of freedom.

Structural dynamics is a subset of structural analysis which covers the behavior of structures subjected to dynamic loading. The subject has seen rapid growth and also change in how the basic concepts can be interpreted. For instance, the classical notions of discretizing the operator of a dynamic structural model have given way to a set-theoretic, function-space based framework, which is more conducive to implementation with a computer. This modern perspective, as adopted in this book, is also helpful in putting together the various tools and ideas in a more integrated style. Elements of Structural Dynamics: A New Perspective is devoted to covering the basic concepts in linear structural dynamics, whilst emphasizing their mathematical moorings and the associated computational aspects that make their implementation in software possible. Key features: Employs a novel ‘top down'approach to structural dynamics. Contains an insightful treatment of the computational aspects, including the finite element method, that translate into numerical solutions of the dynamic equations of motion. Consistently touches upon the modern mathematical basis for the theories and approximations involved. Elements of Structural Dynamics: A New Perspective is a holistic treatise on structural dynamics and is an ideal textbook for senior undergraduate and graduate students in Mechanical, Aerospace and Civil engineering departments. This book also forms a useful reference for researchers and engineers in industry.

This second edition follows the previous one after about two years. Apart from correcting a number of printing errors, few additions have been introduced. In the chapter on the finite element method, a short summary on finite elements in time (four-dimensional finite elements) has been introduced. In the chapter on rotordynamics, two new graphical representations are used; namely, the roots locus plot for free whirling and a tri-dimensional plot for the forced response for which the designation of'orbital tubes'has been proposed. The former has been borrowed from controlled systems dynamics, where it is widely used, while the latter is made practical by the availability of powerful graphical tools for postprocessing numerical or experimental results. As a last point, a more detailed description of the behaviour of magnetic bearings has been introduced in Chapter 6. Torino, September 1994 G. Genta Preface The present book originates from the need felt by the author to give a systematic form to the contents of the lectures he gives to mechanical and aeronautical engineering students of the Technical University (Politecnico) of Torino, within the frames of the courses of Principles and Methodologies of Mechanical Design and Construction of Aircraft Engines. Its main aim is that of summarizing the funda­ mentals of mechanics of vibrations to give the needed theoretical background to the engineer who has to deal with vibration analysis and to show a number of design applications of the theory.

Das Buch vereint in seiner Neuauflage die beiden Bände „Strukturdynamik I und II“ von R. Gasch und K. Knothe. Es behandelt schwingungsfähige Systeme und beschreibt Analyseverfahren und Algorithmen zur Aufstellung von Bewegungsdifferenzialgleichungen allgemeiner linearer Mehrkörpersysteme. Zunächst werden diskrete schwingungsfähige Systeme von wenigen Freiheitsgraden bis hin zu komplexen Mehrkörpersystemen vorgestellt. Kontinuierliche Schwinger und numerische Verfahren zu ihrer Diskretisierung sind weitere Schwerpunkte des Buches. Berechnungsverfahren, wie FEM, Übertragungsmatrizen und die modale Behandlung, werden eingehend erläutert. In der Industrie gängige Substrukturtechniken sind mit zahlreichen Beispielen vertreten. Breiter als bisher werden stabilitätsgefährdete, selbsterregungsfähige Systeme beschrieben. Das Buch eignet sich sowohl als Lehrbuch für Hoch- und Fachhochschulen als auch zum Selbststudium für Ingenieure in Forschungseinrichtungen und in der Industrie.

This collection of papers is a state of the art presentation of theories and methods related to the problem of the behaviour of mechanical structures under variable loads beyond their elastic limit In particular, the problems of shakedown, ratchetting, transient and asymptotic cyclic states are addressed. The volume is composed of four chapters devoted to material modelling for cyclic loading conditions; general theory of accommodated states of structures; effects of changes of the geometry on the inelastic structural response; and numerical techniques with applications to particular engineering problems. It was aimed to provide a unified approach in order to understand both inelastic material and structural response under variable loading conditions. The attempt to extend the classical shakedown theory of Melan and Koiter to geometrically non-linear problems is presented in several papers. The industrial application of cyclic plasticity to the analysis and the design of pressure bellows, compensators, turbine disks, or flange connections under thermal and pressure cycles illustrates the great potential of the numerical techniques developed for this purpose using mostly min-max approaches. The treatment of railway problems and the analysis and optimisation of pavements are further examples of important areas of applications. Emphasis was laid on approaches that take into account the fact that loading histories are often not precisely known Therefore, the center of interest lies in other than step by step calculation methods.

From jet engine noise that generates vibrations in the structure of an aircraft, to the sound radiation from the hull of a ship or submarine that makes it identifiable, an understanding of structural acoustics is key in the design process in maritime, automotive, aerospace, and architectural engineering. Building on classic works in the field, Stru

Robots, aerospace structures, active earthquake-damping devices of tall buildings, and active sound suppression are examples of the application of structural dynamics and control methods. This book addresses the structural dynamics and control problems encountered by mechanical, civil, and control engineers. Many problems presented in this book originated in recent applications in the aerospace industry, and have been solved using the approach presented here. Dynamics analysis and controller design for flexible structures require a special approach due to the large size of structural models, and because flexible structure testing and control typically requires massive instrumentation (sensors and actuators). But the rapid development of new technologies and the increased power of computers allows for the formulation and solution of engineering problems that seemed to be unapproachable not so very long ago. The modal approach was chosen in this book. It has a long tradition in structural engineering (see, e.g., [84], [87], and [26]) and is also used in control system analysis, e.g., [93]. Its usefulness, thoroughly tested, does not need extensive justification. Both structural testing and analysis give priority to the modal representation, due to its compactness, simplicity, and explicit physical interpretation. Also, many useful structural properties are properly exposed only in modal coordinates. In this book the modal approach, preferred by structural engineers, is extended into control engineering, giving new analytical results, and narrowing the gap between structural and control analysis.