Vibration isolation performance of simply supported beam installed with a negative stiffness device

The tuned mass damper (TMD) is a classical device interesting for reducing deformations between DOFs without physically connecting them. However, it has a practical limit due to the increase in mass required for improving its performance. A building mass damper (BMD) uses mode coupling to make the upper substructure of a chain-like structure behave as a TMD for the lower substructure, which avoids adding mass to the structure. Unfortunately, near-uniform chain-like structures require isolation of the upper substructure for tuning the BMD, making it impractical for retrofitting existing structures since it is an in-series intervention. This paper proposes and evaluates using an inerter, instead of isolating the upper substructure, to control vibrations through mode coupling in a chain-like structure. From an analytical and numerical study, it was found a significant reduction of lower substructure deformations by implementing solely an inerter and a damper in the upper substructure. The inerter-based approach showed similar performance to the classical BMD with the advantage of being an in-parallel intervention. Therefore, this approach constitutes a practical retrofit to improve the dynamic behavior of existing structures with excessive deformations in a lower substructure whose functionality or esthetics would be compromised if control devices were installed in it.

Section: Parametric Study Through Numerical Solutionsmentioning

confidence: 99%

On the vibration control through mode coupling in a near-uniform chain-like structure using an inerter

Garrido

Domizio

Curadelli

2023

“…Yaleu et al (2021) introduced a HSLD isolator with the auxiliary system to a hinged-hinged beam subjected to an axial and constant moving load for vibration control. Zhang et al (2022) connected a pair of negative stiffness springs to a simply supported beam to isolate the vibration in the low-frequency range. Xie et al (2022) employed QZS resonators to suppress ultralow-frequency flexural waves in beams with periodic attachments, transferring band gaps to lower frequencies with adjustable negative stiffness for broadband suppression.…”

Section: Introductionmentioning

confidence: 99%

Vibration isolation performance of a beam clamped with torsional quasi-zero-stiffness isolator

Tian

Zhang

Chen

et al. 2023

Elastic beam structures connected by hinges are a common basic component of many mechanical systems. In this study, the nonlinear transverse vibration of a beam with one end free and the other end simply supported with a torsion spring is investigated. A torsional quasi-zero-stiffness vibration isolator is employed at the fixed end of the beam for isolating the vibration excitation from the base. Using Hamilton’s principle, the differential equation of motion for the transverse vibration of the beam is obtained, and the natural characteristics of the beam are determined. The dynamic equation of the system is derived by using Galerkin truncation method and the harmonic balance method is adopted to obtain the nonlinear vibration response. Compared with the vibration transmissibility of the beam supported by the equivalent linear torsion spring, the quasi-zero-stiffness vibration isolation system shows superior vibration isolation performance. It is found that the beam fixed with a torsional quasi-zero-stiffness isolator can reduce the first resonant frequency and provide a wide effective isolation range at low frequency, which is rarely affected by the strong nonlinearity. The results would provide an innovative method of introducing the torsional quasi-zero-stiffness isolator into the passive vibration control of continuum system.

“…Duffing-type vibration isolator (Huang and Ji, 2021; Ji and Zhang, 2010; Liu et al, 2022; Zhang et al, 2022), composed of a second-order linear system and a cubic nonlinear stiffness, has been extensively studied by engineers and scholars, due to its rich dynamic behaviors and strong engineering physics simulation capabilities (Lobo et al, 2019). Le and Ahn (2011) fabricated a Duffing-type vehicle seat and studied the static and dynamic characteristics.…”

Section: Introductionmentioning

confidence: 99%

Analytical jump-avoidance criteria of Duffing-type vibration isolation systems under base and force excitations based on concave-convex property

Liu

Peng

et al. 2022

As a representative nonlinear system, Duffing oscillator has wide applications in the field of vibration control. This paper concentrates on the analytical jump criteria problem for a class of Duffing systems based on the concave-convex property. The mechanical model of Duffing-type isolators subjected to various excitations is firstly presented. The defined single critical jump point (SCJP) is proved to be an inflection point based on the concave-convex property of the dynamic response. Moreover, the analytical jump-avoidance criteria under base and force excitations are established. The sensitivities of dynamic parameters are discussed in detail, and several jump characteristics are revealed and explained. It turned out that the SCJP is inherent for Duffing systems. The key advantage is that the proposed jump-avoidance scheme can be used directly and independent of the solved dynamic response. In other words, this scheme provides a pure algebraic method for determining jumps and an accurate range of the adjustable parameters for practical applications. A series of numerical simulations and comparisons are conducted to demonstrate the effectiveness of the proposed analytical judgment method.