Effects of a Tuned Mass Damper on Wind-induced Motions in Tall Buildings PDF Download

Author: Julien Alexandre Laurent Carlot
Publisher:
ISBN:
Category :
Languages : en
Pages : 107

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Book Description
With ever increasing constructability capacities, engineers have found solutions to build taller and taller structures. However, the race for the sky has not only brought up new ways of building, it has also created new problems to face, namely wind-induced motions. In particular, wind loadings are now the source of vibrations in buildings, which have a direct impact on users. While in the past, strength capacities were the main concern, nowadays, human's comfort has become the one of the new primary problems engineers have to face when designing skyscrapers. Several solutions have been developed throughout the years in order to mitigate the response of a building to wind loads, one of which is the Tuned Mass Damper system. This system, which consists of an auxiliary mass added to a structure, significantly reduces motions in high-rise buildings. However, the theory is often based on a harmonic excitation of a building, which is not necessarily the exact representation of wind loads. This paper analyzes the effects of a Tuned Mass Damper on the response of a building to a saw tooth excitation with white noise, which seems to be a better approximation of how wind loads act on tall structures.

Author: Turgut Sarpkaya
Publisher:
ISBN:
Category : Vibration
Languages : en
Pages : 126

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Book Description
This is a concise and comprehensive review of the progress made during the past two decades on vortex induced vibration (VIV) of mostly circular cylindrical structures subjected to steady uniform flow. The critical elements of the evolution of the ideas, theoretical insights, experimental methods, and numerical models are traced systematically; the strengths and weaknesses of the current state of the understanding of the complex fluid/structure interaction are discussed in some detail. Finally, some suggestions are made for further research on VIV. The organization of the paper is given at the end of the next section.

Author: Rhonda Lynne MacDonald
Publisher:
ISBN:
Category : Damping (Mechanics)
Languages : en
Pages : 216

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Book Description

Author: N. Isyumov
Publisher:
ISBN:
Category : Buildings
Languages : en
Pages : 124

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Book Description
Proceedings of a session at the ASCE Convention, held in Seattle, Washington, April 8, 1986. Sponsored by the Aerodynamics Committee of the Aerospace Division and the Wind Effects Committee of the Structural Division of ASCE. This collection contains six papers examining the motions of buildings produced by wind. The trend towards higher structural efficiency and lower cost has resulted in a generation of lighter and more flexible buildings with a lower inherent capacity for energy dissipation or damping. Unfortunately, this trend has produced structures that are more sensitive to the dynamic action of wind. The emphasis in the design of modern tall buildings has therefore shifted to requirements that control building movements or drift and that limit wind-induced accelerations. Two papers deal with the action of wind on two important tall buildings where designers relied on wind tunnel model tests for information on wind-induced loads and building motions. The design of the Columbia Seafirst Center took advantage of economies possible as a result of wind tunnel studies., and viscoelastic dampers were added to limit the building's motion and wind-induced acceleration. The recorded response of the Allied Bank Plaza during Hurricane Alicia is an extremely important contribution to the understanding of the action of wind on tall buildings; this is the only existing record of the response of a major building under the action of design winds. Another paper discusses a survey of structural damping found in tall buildings, presenting typical damping values for steel and concrete buildings and discussing the variability of such estimates and its implication on design. The final papers consider damping systems that can be added to tall buildings in order to limit their motion. The use of tuned mass dampers and viscoelastic damping units is discussed and examples are presented to show their practical effectiveness. The viscoelastic dampers used in the Columbia Seafirst Center are described.

Author: Emil Simiu
Publisher: John Wiley & Sons
ISBN: 1119375886
Category : Technology & Engineering
Languages : en
Pages : 533

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Book Description
Provides structural engineers with the knowledge and practical tools needed to perform structural designs for wind that incorporate major technological, conceptual, analytical and computational advances achieved in the last two decades. With clear explanations and documentation of the concepts, methods, algorithms, and software available for accounting for wind loads in structural design, it also describes the wind engineer's contributions in sufficient detail that they can be effectively scrutinized by the structural engineer in charge of the design. Wind Effects on Structures: Modern Structural Design for Wind, 4th Edition is organized in four sections. The first covers atmospheric flows, extreme wind speeds, and bluff body aerodynamics. The second examines the design of buildings, and includes chapters on aerodynamic loads; dynamic and effective wind-induced loads; wind effects with specified MRIs; low-rise buildings; tall buildings; and more. The third part is devoted to aeroelastic effects, and covers both fundamentals and applications. The last part considers other structures and special topics such as trussed frameworks; offshore structures; and tornado effects. Offering readers the knowledge and practical tools needed to develop structural designs for wind loadings, this book: Points out significant limitations in the design of buildings based on such techniques as the high-frequency force balance Discusses powerful algorithms, tools, and software needed for the effective design for wind, and provides numerous examples of application Discusses techniques applicable to structures other than buildings, including stacks and suspended-span bridges Features several appendices on Elements of Probability and Statistics; Peaks-over-Threshold Poisson-Process Procedure for Estimating Peaks; estimates of the WTC Towers’ Response to Wind and their shortcomings; and more Wind Effects on Structures: Modern Structural Design for Wind, 4th Edition is an excellent text for structural engineers, wind engineers, and structural engineering students and faculty.

Author: Stephen H. Crandall
Publisher: Academic Press
ISBN: 1483269000
Category : Technology & Engineering
Languages : en
Pages : 177

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Book Description
Random Vibration in Mechanical Systems focuses on the fundamental facts and theories of random vibration in a form particularly applicable to mechanical engineers. The book first offers information on the characterization and transmission of random vibration. Discussions focus on the normal or Gaussian random process; excitation-response relations for stationary random processes; response of a single-degree-of-freedom system to stationary random excitation; wide-band and narrow-band random processes; and frequency decomposition of stationary random processes. The text then examines failure due to random vibration, including failure due to first excursion up to a certain level; fatigue failure due to a stationary narrow-band random stress process; failure due to an accumulation of damage; failure due to response remaining above a certain level for too great a fraction of the time; and failure mechanisms. The manuscript is a vital reference for mechanical engineers and researchers interested in random vibration in mechanical systems.

Author: You Lin Xu
Publisher:
ISBN:
Category : Damping (Mechanics)
Languages : en
Pages : 18

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Book Description
Wind tunnel model tests and theoretical analyses were conducted to investigate the effectiveness of tuned mass dampers in suppressing wind- induced tall building motion. The tall building model was a 1:400 scale aeroelastic model of the CAARC Standard Tall Building. This model and the tuned mass damper models of different parameters were designed and tested in a wind tunnel with properly simulated atmospheric boundary layer flow. The aeroelastic tests of the CAARC model demonstrated the effectiveness of the tuned mass damper system in suppressing the dynamic response of the building. The parametric study of passive tuned mass dampers, leading to theoretical analysis and design of an effective and efficient tuned mass damper system, was based on excitation spectra which were directly measured from the wind tunnel model tests. Theoretical results were in good agreement with the test results. The analytical results further indicated that the effectiveness of tuned mass dampers cn be enhanced by the inclusion of an active control system. (author abstract)

Author: Jerome J. Connor
Publisher: Computational Mechanics
ISBN:
Category : Architecture
Languages : en
Pages : 376

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Book Description
This book bridges the gap between conventional structural design and the emerging field of motion based design. Topics covered include optimal stiffness distributions, tuned mass dampers and base isolation systems.

Author: Jerome Connor
Publisher: Springer
ISBN: 3319062816
Category : Technology & Engineering
Languages : en
Pages : 626

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Book Description
This innovative volume provides a systematic treatment of the basic concepts and computational procedures for structural motion design and engineering for civil installations. The authors illustrate the application of motion control to a wide spectrum of buildings through many examples. Topics covered include optimal stiffness distributions for building-type structures, the role of damping in controlling motion, tuned mass dampers, base isolation systems, linear control, and nonlinear control. The book's primary objective the satisfaction of motion-related design requirements such as restrictions on displacement and acceleration and seeks the optimal deployment of material stiffness and motion control devices to achieve these design targets as well as satisfy constraints on strength. The book is ideal for practicing engineers and graduate students.

Author: Zheng Li Gong
Publisher:
ISBN:
Category :
Languages : en
Pages : 102

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Book Description
As tall buildings keep becoming taller, they become more susceptible to dynamic excitations such as wind and seismic excitations. One way to reduce structural vibration under dynamic excitations is by placing damping devices in the buildings. In this thesis, the design concept, design procedure and some current applications of tuned mass and viscous dampers are discussed. Taipei101 was used as an example to compare the performance of the two damping schemes. It was modeled in a two-dimensional scheme in SAP2000 and a TMD was placed on its top to study its effect on the structural response due to wind and seismic excitations and confirm with the actual results. A sensitivity study was then performed to study the effect of varying the mass ratio on the structural response. A second TMD was then placed at the location where the maximum deflection occurs for the second mode to evaluate its effectiveness in reducing structural response. Finally, twelve viscous dampers were placed in the model to study their effects on the structural response. Time-history and steady-state analysis in SAP2000 were used for the wind and seismic analyses.