1st Edition
Structural Damping Applications in Seismic Response Modification
Rapid advances have been made during the past few decades in earthquake response modification technologies for structures, most notably in base isolation and energy dissipation systems. Many practical applications of various dampers can be found worldwide and, in the United States, damper design has been included in building codes. The current design process is simple and useful for adding supplemental damping up to a reasonable level—but it is not as useful with higher levels of damping.
Taking a different approach, Structural Damping: Applications in Seismic Response Modification considers the dynamic responses of structures with added damping devices as systems governed by the combined effect of the static stiffness, period, and damping—or "dynamic stiffness"—of the structure-device system. This formulation supplies additional information for higher-level supplemental damping design that current provisions may not adequately cover. The authors also propose a more comprehensive consideration of the core issues in structural damping, which provides a useful foundation for continued research and development in seismic response modification technologies for performance-based engineering.
The book includes design examples, based on the authors’ research and practical experience, to illustrate approaches that include higher-level supplemental damping to complement the use of the current NEHRP/ASCE-7 provisions. A self-contained resource on damping design principles, this book helps earthquake engineers select the most effective type of damper and determine the amount and configuration of damping under given working conditions.
VIBRATION SYSTEMS
Free and Harmonic Vibration of Single-Degree-of-Freedom Systems
Model of Linear SDOF Vibration Systems
Dynamic Magnification
Energy Dissipation and Effective Damping
Linear Single-Degree-of-Freedom Systems with Arbitrary Excitations
Periodic Excitations
Transient Excitations
Random Excitations
Earthquake Responses of SDOF Linear Systems
Linear Proportionally Damped Multi-Degree-of-Freedom Systems
Undamped MDOF Systems
Proportionally Damped MDOF Systems
Modal Participation and Truncation
Base Shear and Lateral Force
Natural Frequency and Mode Shape Estimation
Coefficient Matrix for Proportional Damping
Multi-Degree-of-Freedom Systems with General Damping
State Equation and Conventional Treatment
Damper Design for Nonproportionally Damped Systems
Overdamped Subsystems
Responses of Generally Damped Systems and the Design Spectra
Modal Participations and Modal Criteria
PRINCIPLES AND GUIDELINES FOR DAMPING CONTROL
Principles of Damper Design
Modeling of Damping
Rectangular Law, Maximum Energy Dissipation per Device
Damping Adaptability
Design and Control Parameters
Damping Force-Related Issues
System Nonlinearity and Damping of Irregular Structures
Nonlinear Systems
Irregular MDOF System
Minimizing Damping Nonproportionality
Role of Damping in Nonlinear Systems
DESIGN OF SUPPLEMENTAL DAMPING
Linear Damping Design
Overview of Design Approaches
MSSP Systems Simplified Approach
Proportionally Damped MDOF Systems Approach
Design of Generally Damped Systems
Damper Design Issues
Damper Design Codes
Brief Summary of Damping Design of Linear Systems
Nonlinear Damping
Overview of Design Approaches
Equivalent Linear Systems Approach with Bilinear Dampers
Equivalent Linear Systems Approach with Sublinear Dampers
Nonlinear Response Spectra Approach with Sublinear Dampers
Nonlinear Response Spectra Approach with Bilinear Dampers
Index
Chapters include a summary and references.
Biography
Dr. Zach Liang is a research professor in the Department of Mechanical and Aerospace Engineering at the State University of New York at Buffalo.
Dr. George C. Lee is a SUNY Distinguished Professor in the Department of Civil, Structural and Environmental Engineering at the State University of New York at Buffalo.
Dr. Gary F. Dargush is Professor and Chair of the Department of Mechanical and Aerospace Engineering (MAE) at the State University of New York at Buffalo.
Dr. Jianwei Song is a senior research scientist in the Multidisciplinary Center for Earthquake Engineering Research in the Department of Civil, Structural and Environmental Engineering at the State University of New York at Buffalo.