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Structural Vibration Control Using Passive Devices
Published in Suhasini Madhekar, Vasant Matsagar, Passive Vibration Control of Structures, 2022
Suhasini Madhekar, Vasant Matsagar
Structural vibrations caused by earthquake or wind can be controlled by various means, such as by modifying rigidities, masses, damping or shape and by providing passive or active counter forces. Vibration control plays a vital role in increasing the safety and performance requirements of structures subjected to dynamic loads. Structural vibrations can be controlled effectively by implementing appropriate control strategies and installing energy-dissipating devices into the structures. The structure then relies on its own strength to withstand dynamic forces, and on the control devices to dissipate energy. Vibration control techniques are mainly categorized as passive, active, semi-active, and hybrid systems. Thus, the structural control systems (also known as earthquake protection systems) passively, actively, or semi-actively suppress the oscillations in the structure. The basic objective of structural control is to reduce response of the structure under dynamic loading, so that: (i) the damage induced to the structure remains minimal and (ii) the vibration limits of desired serviceability criteria are satisfied. The control of the vibration can be achieved by: (i) reducing magnitude input to the structure from ground acceleration through the use of base isolation systems, (ii) dissipation of the energy by providing dampers in the structure, and (iii) avoiding resonance by altering the dynamic properties of the structure by using stiffness-control devices.
Collective placement of control devices and sensors
Published in You-Lin Xu, Jia He, Smart Civil Structures, 2017
In practice, the responses to be measured as feedbacks for vibration control of a building structure under earthquake excitation are often the absolute acceleration responses, which can be directly measured by accelerometers. The corresponding observation equation of the controlled building structure can then be written as () Y=CcX+FcU
Vibration Control
Published in David A. Bies, Colin H. Hansen, Carl Q. Howard, Engineering Noise Control, 2018
David A. Bies, Colin H. Hansen, Carl Q. Howard
The second form of vibration control is modification of the dynamic characteristics (or mechanical input impedance) of a structure to reduce its ability to respond to the input energy; thus, essentially suppressing the transfer of vibrational energy from the source to the noise-radiating structure. This may be achieved by stiffness or mass changes to the structure or by use of a vibration absorber. Alternatively, the radiating surface may be modified to minimise the radiation of sound to the environment. This may sometimes be done by choice of an open structure, for example, a perforated surface instead of a solid surface.
Active vibration control of composite laminates with MFC based on PID-LQR hybrid controller
Published in Mechanics of Advanced Materials and Structures, 2023
Hui Zhang, Wei Sun, Haitao Luo, Rongfei Zhang
Currently, the structural vibration control methods mainly include passive and active control. Passive control does not depend on the intervention of external energy, generally through the dampers to absorb energy or increase the damping of the structure to dissipate vibration energy to achieve the effect of structural vibration suppression. For example, Chen and Huang [8] achieved passive control of the structure by performing constrained layer damping (CLD) treatment on a rectangular plate and determined the optimal location for the CLD treatment on the structure. Ribeiro et al. [9] implemented robust passive vibration control of composite beams based on a resonant parallel shunt circuit. Kumar and Singh [10] used an additional constrained layer damping patch on the surface of the curved panel to achieve passive damping of the structure. Bodaghi et al. [11] investigated the passive vibration control of integrated shape memory alloy (SMA) rectangular plates under low and high-temperature dynamic loads. Although there are many kinds of research on passive control, its application is limited due to the defects of passive control, such as the poor self-adaptive ability to cope with complex working conditions and large weight gain without meeting the requirements of structural lightweight.
Nonlinear vibrations of fractional nonlocal viscoelastic nanotube resting on a Kelvin–Voigt foundation
Published in Mechanics of Advanced Materials and Structures, 2022
Nowadays, the nanotubes are frequently used to reinforce structures. Because of the destroying effect of vibrations on the structures, vibration control is a topic increasingly addressed by the researchers. The investigations on the free vibration analysis of a nanobeam resting on an elastic foundation appear in [7, 8] and those embedded in viscoelastic medium are presented in the articles [9–11]. In the dynamic analysis of the nanostructures, a special interest has the nonlocal mechanics theory, which was established by Eringen [12] and first used for nanomechanics of SWCNT’s by Peddieson et al. [13] and Sudak [14]. The nonlocal theory states that the stress at a reference point is affected not only by the strain at that point but also by the strains at every point of the domain [15]. Nonlocal calculation is approached more and more often for modeling of the vibrations of the CNT resonators [16] and finding of the asymptotic frequencies, which are obtained for the undamped and damped Timoshenko beams [17].
Mechanical hysteresis model of a metal-wire Kagome truss for seismic strengthening for building systems
Published in Journal of Asian Architecture and Building Engineering, 2019
Jae-Seung Hwang, Kang-Seok Lee, Moo-Won Hur, Sang-Hyun Lee
Inspired by such concerns, vibration control technology has been recently introduced and utilized in seismic design. The recent seismic design code separates the damping system from the earthquake-resisting system (ASCE 2010). Vibration control is a method that uses a separate structural member or device, with excellent energy dissipation capacity, to protect other structural members. Vibration control can be achieved using passive, active, and semi-active control systems applied to the external power supply, computer, and sensors. Because it may be hard to supply external energy at a stable rate during an earthquake event, passive or semi-active vibration control systems have mainly been used. Passive energy dissipation devices include fluid viscous dampers (Lee and Taylor 2002), viscoelastic dampers (Abbas and Kelly 1993), friction dampers (Wu et al. 2005), and hysteric metallic dampers (Dargush and Soong 1995), and are classified according to the intrinsic properties and energy absorption mechanisms of the materials composing the device. These dampers are further categorized as displacement- or velocity-dependent dampers, depending on the force–response relationship.