A parametric study on reliability-based tuned-mass damper design against bridge flutter

2015 ◽  
Vol 23 (9) ◽  
pp. 1518-1534 ◽  
Author(s):  
Filippo Ubertini ◽  
Gabriele Comanducci ◽  
Simon Laflamme
Keyword(s):  
Design Procedure ◽  
Tuned Mass Damper ◽  
Computationally Efficient ◽  
Long Span Bridges ◽  
Long Span ◽  
Mass Damper ◽  
Supplemental Damping ◽  
Damper Design ◽  
Reducing Costs ◽  
First Order Method

We present a probabilistic methodology for designing tuned mass dampers for flutter suppression in long-span bridges. The procedure is computationally efficient and computes the probability of flutter occurrence based on a modified first-order method of reliability analysis, a reduced-order representation of the structure and a time domain formulation of aeroelastic loads. Results of a parametric investigation show that the proposed methodology is preferable to a deterministic design procedure, which relies on nominal values of mechanical and aerodynamic parameters and does not guarantee the maximum safety. Furthermore, the reliability-based approach can be effectively used in the design of multiple tuned mass damper configurations by enhancing robustness against frequency mistuning and by reducing costs associated with supplemental damping for a given safety performance level.

A new approach to inertial damper design to control base displacement in isolated buildings

2021 ◽  
pp. 107754632110359
Author(s):  
César A Morales
Keyword(s):  
Vibration Isolation ◽  
Design Procedure ◽  
Optimization Method ◽  
Tuned Mass Damper ◽  
Tuned Mass Dampers ◽  
Seismic Displacement ◽  
Displacement Problem ◽  
Mass Damper ◽  
Damper Design ◽  
Base Displacement

A novel design procedure for tuned mass dampers in isolated structures is presented. The proposed optimization method is specifically developed to control base displacements or to solve the large isolator displacement problem in this type of structures under earthquakes. Therefore, it is based on a displacement transmissibility function, T, a particular case of the general transmissibility concept, which comes from Vibration Isolation. Three contributions are application of new seismic displacement narrowbandness, simpler relative transmissibility function, and compound design of isolation plus tuned mass damper. A standard isolated model is used to show that the base displacement can be controlled at levels in the proximity of the ground motion ( T ≈ 1), which results in a positive comparison with previous isolation and tuned mass damper solutions; this is one of the main conclusions and it is based on novelty three above; in fact, other solutions in the literature compare their attained displacements with respect to the structure without tuned mass damper. Comparison with isolated results is not, therefore, possible herein, but it is not desirable either; actually, what is possible is a positive and more demanding comparison, which is with respect to the very seismic ground displacement itself. The large isolator displacement problem can be solved or attenuated by properly designing a tuned mass damper subsystem jointly with the isolation one.

A novel tuned mass-conical spring system for passive vibration control of a variable mass structure

2021 ◽  
pp. 107754632110004
Author(s):  
Sanjukta Chakraborty ◽  
Aparna (Dey) Ghosh ◽  
Samit Ray-Chaudhuri
Keyword(s):  
Variable Mass ◽  
Design Procedure ◽  
Time History ◽  
Tuned Mass Damper ◽  
Water Tank ◽  
Mass System ◽  
Mass Damper ◽  
Linear Spring ◽  
Spring System ◽  
Elevated Water

This article presents the design of a tuned mass damper with a conical spring to enable tuning to the natural frequency of the system at multiple values, as may be convenient in case of a system with fluctuations in the mass. The principle and design procedure of the conical spring in the context of a varying mass system are presented. A passive feedback control mechanism based on a simple pulley-mass system is devised to cater to the multi-tuning requirements. A design example of an elevated water tank with fluctuating water content, subjected to ground excitation, is considered to numerically illustrate the efficiency of such a tuned mass damper associated with the conical spring. The conical spring is designed based on the tuning requirements at different mass conditions of the elevated water tank by satisfying the allowable load bearing capacity of the spring. Comparisons are made with the conventional passive tuned mass damper with a linear spring tuned to the full tank condition. Results from time history analysis reveal that the conical spring-tuned mass damper can be successfully designed to remain tuned and thereby achieve significant response reductions under stiffening conditions of the primary structure, whereas the linear spring-tuned mass damper suffers performance degradation because of detuning, whenever there is any fluctuation in the system mass.

scholarly journals Tuned Mass Damper Design for Slender Masonry Structures: A Framework for Linear and Nonlinear Analysis

2021 ◽  
Vol 11 (8) ◽  
pp. 3425
Author(s):  
Marco Zucca ◽  
Nicola Longarini ◽  
Marco Simoncelli ◽  
Aly Mousaad Aly
Keyword(s):  
Nonlinear Analysis ◽  
Linear Time ◽  
Design Procedure ◽  
Time History ◽  
Tuned Mass Damper ◽  
Second Phase ◽  
Masonry Structures ◽  
Base Shear ◽  
Mass Damper ◽  
Linear And Nonlinear

The paper presents a proposed framework to optimize the tuned mass damper (TMD) design, useful for seismic improvement of slender masonry structures. A historical masonry chimney located in northern Italy was considered to illustrate the proposed TMD design procedure and to evaluate the seismic performance of the system. The optimization process was subdivided into two fundamental phases. In the first phase, the main TMD parameters were defined starting from the dynamic behavior of the chimney by finite element modeling (FEM). A series of linear time-history analyses were carried out to point out the structural improvements in terms of top displacement, base shear, and bending moment. In the second phase, masonry's nonlinear behavior was considered, and a fiber model of the chimney was implemented. Pushover analyses were performed to obtain the capacity curve of the structure and to evaluate the performance of the TMD. The results of the linear and nonlinear analysis reveal the effectiveness of the proposed TMD design procedure for slender masonry structures.

scholarly journals Development of a Frequency-Adjustable Tuned Mass Damper (FATMD) for Structural Vibration Control

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Huaguo Gao ◽  
Congbao Wang ◽  
Chen Huang ◽  
Wenlong Shi ◽  
Linsheng Huo
Keyword(s):  
Damping Ratio ◽  
Tuned Mass Damper ◽  
Vertical Vibration ◽  
Structural Vibration ◽  
Kinematic Equation ◽  
Pedestrian Bridge ◽  
Long Span ◽  
Mass Damper ◽  
Excitation Frequencies ◽  
Simple Assembly

The tuned mass damper (TMD) can be applied to suppress earthquake, wind, and pedestrian- and machine-induced vibration in factory buildings or large span structures. However, the traditional TMD with a fixed frequency will not be able to perform effectively against the frequency variations in multiple hazards. This paper proposed a frequency-adjustable tuned mass damper (FATMD) to solve this limitation of current TMD. The FATMD presented in this paper is composed of a simple assembly consisting of a supported beam with a mass, in which the frequency of the FATMD is changed by adjusting the span of the beam. The kinematic equation of a single degree of freedom (SDOF) structure installed with an FATMD is established to analyze the effect of the damping ratio, mass ratio, and stiffness on the vibration damping. The fundamental frequency of the FATMD at different spans is verified by simulation and experiments. Forced vibration experiments with different excitation frequencies are also conducted to verify the performance of the FATMD. The results show that the proposed FATMD can effectively suppress the vertical vibration of structures at different excitation frequencies, including frequencies at a range higher than what a traditional TMD may not be able to suppress. Additionally, the proposed FATMD is applied to a long-span pedestrian bridge which vibrates frequently due to the walking of pedestrians, the running of escalators, and earthquakes. The numerical results indicate that the FATMD can effectively reduce the vertical vibration of the pedestrian bridge under the excitations of pedestrians, escalators, and earthquakes.

Robust multi-objective optimization design of active tuned mass damper system to mitigate the vibrations of a high-rise building

2014 ◽  
Vol 229 (1) ◽  
pp. 26-43 ◽  
Author(s):  
S Pourzeynali ◽  
S Salimi
Keyword(s):  
Damping Ratio ◽  
Tuned Mass Damper ◽  
Robust Design Optimization ◽  
Design Parameters ◽  
Control Force ◽  
Multi Objective ◽  
High Rise ◽  
High Rise Building ◽  
Mass Damper ◽  
Damper Design

In engineering applications, many control devices have been developed to reduce the vibrations of structures. Active tuned mass damper system is one of these devices, which is a combination of a passive tuned mass damper system and an actuator to produce a control force. The main objective of this paper is to present a practical procedure for both deterministic and probabilistic design of the active tuned mass damper control system using multi-objective genetic algorithms to mitigate high-rise building responses. For this purpose, extensive numerical analyses have been performed, and optimal robust results of the active tuned mass damper design parameters with their effectiveness in reducing the example building responses have been presented. Uncertainties, which may exist in the system, have been taken into account using a robust design optimization procedure. The stiffness matrix and damping ratio of the building are considered as uncertain random variables; and using the well-known beta distribution, 50 pairs of these variables are generated. This resulted in 50 buildings with different stiffness matrices and damping ratios. These simulated buildings are used to evaluate robust optimal values of the active tuned mass damper design parameters. Four non-commensurable objective functions, namely maximum displacement, maximum velocity, maximum acceleration of each floor of the building, and active control force produced by the actuator are considered, and a fast and elitist non-dominated sorting genetic algorithm approach is used to find a set of pareto-optimal solutions.

Sign in / Sign up

Export Citation Format

Share Document