Technology Of Semiactive Devices And Applications In Vibration Mitigation

Researchers have studied many methods of using active and passive control devices for absorbing vibratory energy. Active devices, while providing significant reductions in structural motion, typically require large (and often multiply-redundant) power sources, and thereby raise concerns about stability. Passive devices are fixed and cannot be modified based on information of excitation or structural response. Semiactive devices on the other hand can provide significant vibration reductions comparable to those of active devices but with substantially reduced power requirements and in a stable manner. Technology of Semiactive Devices and Applications in Vibration Mitigation presents the most up-to-date research into semiactive control systems and illustrates case studies showing their implementation and effectiveness in mitigating vibration. The material is presented in a way that people not familiar with control or structural dynamics can easily understand. Connecting structural dynamics with control, this book: Provides a history of semiactive control and a bibliographic review of the most common semiactive control strategies. Presents state-of-the-art semiactive control systems and illustrates several case studies showing their implementation and effectiveness to mitigate vibration. Illustrates applications related to noise attenuation, wind vibration damping and earthquake effects mitigation amongst others. Offers a detailed comparison between collocated and non-collocated systems. Formulates the design concepts and control algorithms in simple and readable language. Includes an appendix that contains critical considerations about semiactive devices and methods of evaluation of the original damping of a structure. Technology of Semiactive Devices and Applications in Vibration Mitigation is a must-have resource for researchers, practitioners and design engineers working in civil, automotive and mechanical engineering. In addition it is undoubtedly the key reference for all postgraduate students studying in the field.

Book presents a comprehensive coverage of the area of vibration control of civil structures subjected to different types of loading while using passive, semi-active, and/or active controls. Presents the theoretical governing equations as well as the associated design guides of various vibration control mitigation approaches. Discusses structural monitoring aspects such as sensor technology, system identification and signal processing topics. Reviews structural control aspects, such as algorithms. Includes solved examples utilizing MATLAB®/SIMULINK® with source codes of the calculation examples and design tool set.

This book focuses on the important and diverse field of vibration analysis and control. It is written by experts from the international scientific community and covers a wide range of research topics related to design methodologies of passive, semi-active and active vibration control schemes, vehicle suspension systems, vibration control devices, fault detection, finite element analysis and other recent applications and studies of this fascinating field of vibration analysis and control. The book is addressed to researchers and practitioners of this field, as well as undergraduate and postgraduate students and other experts and newcomers seeking more information about the state of the art, challenging open problems, innovative solution proposals and new trends and developments in this area.

This book proposes, for the first time, a basic formulation for structural control that takes into account the stochastic dynamics induced by engineering excitations in the nature of non-stationary and non-Gaussian processes. Further, it establishes the theory of and methods for stochastic optimal control of randomly-excited engineering structures in the context of probability density evolution methods, such as physically-based stochastic optimal (PSO) control. By logically integrating randomness into control gain, the book helps readers design elegant control systems, mitigate risks in civil engineering structures, and avoid the dilemmas posed by the methods predominantly applied in current practice, such as deterministic control and classical linear quadratic Gaussian (LQG) control associated with nominal white noises.

Seismic Evaluation, Damage, and Mitigation in Structures covers recent developments in the field of seismic performance assessment of structures. Earthquakes are one of the main natural hazards that can directly cause damage to a structure or even instigate a structural collapse, resulting in significant economic and human loss of life. In the event of an earthquake where many buildings and infrastructure components are not able to function afterward, or if extensive repair and associated disruption are needed, it can be extremely costly and take a long time to resolve. Divided into three parts, this book reviews and discusses earthquake-induced damage evaluation in structures, the repair of structural and non-structural components, and seismic damage mitigation strategies. With contributions from the leading experts in the field, this book is for earthquake engineers, structural engineers, PhD students studying civil engineering, people who can easily inspect and repair structures for quick reoccupation, and for those who understand topics such as design and damage mitigation, and limited structural or non-structural damage in seismic events. Provides effective and economical methods to assess the seismic performance of structures Analyzes earthquake damage and repair or demolition of buildings Offers future needs for constructing seismic resistant structures

Mechanics and model-based control are both rapidly expanding scientific fields and fundamental disciplines of mechatronics, sharing demanding mathematical and system-theoretic formulations and methods. The papers in this volume deal with smart materials, which allow the design and implementation of new types of actuator/sensor fields and networks. Main topics treated are fundamental studies on laminated, composite and functionally graded materials, thermal and piezoelectric actuation, active and passive damping, as well as vibrations and waves in smart structures. The book is based on the 1st Japanese-Austrian Workshop which took place in Linz in Fall 2008.

​The book addresses the topic of on-line implementation of structural and mechanical design criteria as an explicit part of optimal control schemes. The intention of the present research monograph is to reflect recent developments within this area. Examples of application of relevant control algorithms are included to illustrate their practical implementation. These examples are mainly taken from the area of marine technology with the multi-component external loading being represented as both varying in time and with magnitudes that are represented as statistical quantities. The relevant target group will be mechanical and structural engineers that are concerned with “smart components and structures” where optimal design principles and control actuators are combined. The book is also relevant for engineers e.g. involved in mechatronics and control applications.

In Stochastic Dynamics of Structures, Li and Chen present a unified view of the theory and techniques for stochastic dynamics analysis, prediction of reliability, and system control of structures within the innovative theoretical framework of physical stochastic systems. The authors outline the fundamental concepts of random variables, stochastic process and random field, and orthogonal expansion of random functions. Readers will gain insight into core concepts such as stochastic process models for typical dynamic excitations of structures, stochastic finite element, and random vibration analysis. Li and Chen also cover advanced topics, including the theory of and elaborate numerical methods for probability density evolution analysis of stochastic dynamical systems, reliability-based design, and performance control of structures. Stochastic Dynamics of Structures presents techniques for researchers and graduate students in a wide variety of engineering fields: civil engineering, mechanical engineering, aerospace and aeronautics, marine and offshore engineering, ship engineering, and applied mechanics. Practicing engineers will benefit from the concise review of random vibration theory and the new methods introduced in the later chapters. "The book is a valuable contribution to the continuing development of the field of stochastic structural dynamics, including the recent discoveries and developments by the authors of the probability density evolution method (PDEM) and its applications to the assessment of the dynamic reliability and control of complex structures through the equivalent extreme-value distribution." —A. H-S. Ang, NAE, Hon. Mem. ASCE, Research Professor, University of California, Irvine, USA "The authors have made a concerted effort to present a responsible and even holistic account of modern stochastic dynamics. Beyond the traditional concepts, they also discuss theoretical tools of recent currency such as the Karhunen-Loeve expansion, evolutionary power spectra, etc. The theoretical developments are properly supplemented by examples from earthquake, wind, and ocean engineering. The book is integrated by also comprising several useful appendices, and an exhaustive list of references; it will be an indispensable tool for students, researchers, and practitioners endeavoring in its thematic field." —Pol Spanos, NAE, Ryon Chair in Engineering, Rice University, Houston, USA