Seismic performances of a structure equipped with a large mass ratio multiple tuned mass damper

Tuned mass dampers (TMD) are one of the most reliable devices to control the vibration of the structure. The optimum mass ratio required for a single tuned mass damper (STMD) is evaluated corresponding to the fundamental natural frequency of the structure. The effect of STMD and Multiple tuned mass dampers (MTMD) on a G+20 storey structure are studied to demonstrate the damper’s effectiveness in seismic application. The location and number of tuned mass dampers are studied to give best structural performance in maximum reduction of seismic response for El Centro earthquake data. The analysis results from SAP 2000 software tool shows damper weighing 2.5% of the total weight of the structure effectively reduce the response of the structure. Study shows that introduction of 4-MTMD at top storey can effectively reduce the response by 10% more in comparison to single tuned mass damper. The use of MTMD of same mass ratio that of STMD is more effective in seismic response.

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Analysis study the used of Tuned Mass Damper (TMD) on an existing train bridge due to high speed train with moving mass load approach

MATEC Web of Conferences ◽

10.1051/matecconf/201925805005 ◽

2019 ◽

Vol 258 ◽

pp. 05005 ◽

Cited By ~ 1

Author(s):

Wivia Octarena Nugroho ◽

Dina Rubiana Widarda ◽

Oryza Herdha Dwyana

Keyword(s):

High Speed ◽

Tuned Mass Damper ◽

Dynamic Responses ◽

Mass Ratio ◽

High Speed Train ◽

Maximum Deformation ◽

Mass Load ◽

Mass Damper ◽

Existing Bridges ◽

Comfort Criteria

As the need of the train speed increased, the existing bridges need to be evaluated, especially in dynamic responses, which are deformation and acceleration. In this study, Cisomang Bridge is modeled and analyzed due to the high-speed train SJ X2 in varying speeds, 50 km/h, 100 km/h, 150 km/h, and 200 km/h. The used of tuned mass damper also will be varied on its setting and placing. The tuned mass dampers setting be varied based on the first or second natural frequency and the placing of tuned mass damper be varied based on maximum deformation of the first or second mode. Moreover, the tuned mass damper ratio will be varied 1% and 1.6%. For all speed variations, dynamic responses of structure without TMD still fulfil the Indonesian Government Criterion based on PM 60 - 2012 but do not meet requirement of comfort criteria based on DIN-Fachbericht 101. Furthermore, only for the speed train 50km/h dynamic responses of structure fulfil safety criteria based on Eurocode EN 1990:2002, whereas the other speed variations do not meet that requirement. In the use of TMD 1% mass ratio, the structure fulfils the safety criteria for all speed variations. In the use of TMD 1.6% mass ratio, all the structure fulfils the safety and comfort criteria except 100 km/h speed which only fulfils the safety criteria.

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Forming bulges during galaxy minor mergers

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308017298 ◽

2007 ◽

Vol 3 (S245) ◽

pp. 63-66 ◽

Cited By ~ 2

Author(s):

T. J. Cox ◽

J. Younger ◽

L. Hernquist ◽

P. F. Hopkins

Keyword(s):

Black Hole ◽

Large Mass ◽

Elliptical Galaxies ◽

Equal Mass ◽

Mass Ratio ◽

Black Hole Growth ◽

Major Merger ◽

Hole Growth ◽

Minor Mergers ◽

Large Mass Ratio

AbstractThe hierarchical formation of structure suggests that dark halos, and the galaxies they host, are shaped by their merging history. While the idea that mergers between galaxies of equal mass, i.e., major merger, produce elliptical galaxies has received considerable attention, he galaxies that result from minor merger, i.e., mergers between galaxies with a large mass ratio, is much less understood. We have performed a large number of numerical simulations of minor mergers, including cooling, star formation, and black hole growth in order to study this process in more detail. This talk will present some preliminary results of this study, and in particular, the morphology and kinematics of minor merger remnants.

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HD 53975: an O-type spectroscopic binary with a large mass ratio

The Astrophysical Journal ◽

10.1086/173774 ◽

1994 ◽

Vol 422 ◽

pp. 823 ◽

Cited By ~ 12

Author(s):

D. R. Gies ◽

A. W. Fullerton ◽

C. T. Bolton ◽

W. G., Jr. Bagnuolo ◽

M. E. Hahula ◽

...

Keyword(s):

Large Mass ◽

Mass Ratio ◽

Spectroscopic Binary ◽

Large Mass Ratio

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Flutter Characteristics of a Sheet in the Case of Large Mass Ratio

The Proceedings of Mechanical Engineering Congress Japan ◽

10.1299/jsmemecj.2016.j0910301 ◽

2016 ◽

Vol 2016 (0) ◽

pp. J0910301

Author(s):

Shotaro ISHIHARA ◽

Keiichi HIROAKI ◽

Masahiro WATANABE

Keyword(s):

Large Mass ◽

Mass Ratio ◽

Large Mass Ratio

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Analysis of Load Reduction of Floating Wind Turbines Using Passive Tuned Mass Dampers

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.38179 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1340-1345

Author(s):

Aabas Ahmad

Keyword(s):

Standard Deviation ◽

Wind Turbine ◽

Tuned Mass Damper ◽

Mass Ratio ◽

Longitudinal Displacement ◽

Wave Load ◽

Tuned Mass Dampers ◽

Floating Wind Turbine ◽

Mass Damper ◽

Offshore Floating Wind Turbine

Abstract: An efficient method for restraining the large vibration displacements and loads of offshore floating wind turbines under harsh marine environment is proposed by putting tuned mass dampers in the cabin. A dynamics model for a barge-type offshore floating wind turbine with a fore–aft tuned mass damper is established based on Lagrange’s equations; the nonlinear least squares Leven berg–Marquardt algorithm is employed to identify the parameters of the wind turbine; different parameter optimization methods are adopted to optimize tuned mass damper parameters by considering the standard deviation of the tower top longitudinal displacement as the objective function. Aiming at five typical combined wind and wave load cases under normal running state of the wind turbine, the dynamic responses of the wind turbine with/without tuned mass damper are simulated and the suppression effect of the tuned mass damper is investigated over the wide range of load cases. The results show that when the wind turbine vibrates in the state of damped free vibration, the standard deviation of the tower top longitudinal displacement is decreased approximately 60% in 100 s by the optimized tuned mass damper with the optimum tuned mass damper mass ratio 1.8%. The standard deviation suppression rates of the longitudinal displacements and loads in the tower and blades increase with the tuned mass damper mass ratio when the wind turbine vibrates under the combined wind and wave load cases. When the mass ratio changes from 0.5% to 2%, the maximum suppression rates vary from 20% to 50% correspondingly, which effectively reduce vibration responses of the offshore floating wind turbine. The results of this article preliminarily verify the feasibilities of using a tuned mass damper for restraining vibration of the barge-type offshore floating wind turbine

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A Hybrid Tuned Mass Damper for Response Mitigation of Offshore Platforms

10.21203/rs.3.rs-1230815/v1 ◽

2022 ◽

Author(s):

Quoc Huong Cao

Keyword(s):

Vibration Control ◽

Tuned Mass Damper ◽

Offshore Platforms ◽

Structural Stiffness ◽

Mass Ratio ◽

Structural Vibrations ◽

Numerical Computations ◽

Tuned Liquid Column Damper ◽

Parametric Investigation ◽

Mass Damper

Abstract A new hybrid type of the Tuned Mass Damper (HTMD), which consists of a Tuned Liquid Column Damper (TLCD) fixed on the top of a traditional Tuned Mass Damper (TMD), is developed for vibration control of an offshore platform. The results obtained from the parametric investigation show that the mass ratio between TLCD and TMD significantly affects the HTMD's performance. To assess the effectiveness and robustness of HTMD, extensive comparisons are made between an optimized HTMD and an optimum TMD with the same weight as the HTMD. The numerical computations indicate that the proposed HTMD offers a higher level of effectiveness in suppressing structural vibrations compared with a traditional TMD. However, the optimum HTMD is not robust in resisting the variation of the structural stiffness.

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