Author: Sukit ThepmongkornPublisher:
ISBN:
Category : Tall buildings
Languages : en
Pages : 480
Book Description
Wind-induced Coupled and Complex Motions of Tall Buildings
Author: Sukit ThepmongkornPublisher:
ISBN:
Category : Tall buildings
Languages : en
Pages : 480
Book Description
Wind-induced Dynamic Response of Tall Buildings with Coupled 3D Modes of Vibration
Author: David Yun Nin YipPublisher:
ISBN:
Category : Buildings
Languages : en
Pages : 256
Book Description
A Preliminary Analysis of Wind Induced Coupled Motion in Tall Buildings
Author: Supat PoopakaPublisher:
ISBN:
Category : Buildings
Languages : en
Pages : 58
Book Description
Estimation of Wind-Induced Dynamic Responses of Tall Buildings of Non-Ideal Mode Shapes by Time Domain Analysis
Author: AI. LIPublisher:
ISBN: 9781361429297
Category :
Languages : en
Pages :
Book Description
This dissertation, "Estimation of Wind-induced Dynamic Responses of Tall Buildings of Non-ideal Mode Shapes by Time Domain Analysis" by Ai, Li, 李愛, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled ESTIMATION OF WIND-INDUCED DYNAMIC RESPONSES OF TALL BUILDINGS OF NON-IDEAL MODE SHAPES BY TIME DOMAIN ANALYSIS submitted by LI Ai for the degree of Master of Philosophy at The University of Hong Kong in September 2007 Modern architectural building design is becoming increasingly complex, and must take into account aesthetic considerations or land availability all over the world. Many buildings possess extraordinary shapes and spectacular dynamic characteristics which make them vulnerable to extreme wind events. Therefore, wind-induced response assessment exerts an important influence on the structural specifications of tall buildings during the design processes. Ad-hoc wind tunnel modelling is widely used for tall building design. In particular, the high frequency force balance (HFFB) technique has gained wide popularity. This technique assumes ideal building mode shapes, which are linear in translational directions and constant in torsion. However, this assumption does not hold good for most realistic structures of complex properties. Furthermore, the force balance technique does not give information on the vertical distribution pattern of wind loads along the building height. The present study aims to develop a wind tunnel technique to assess wind-induced responses of a tall building with complex dynamic characteristics. Time histories of the wind loads on various levels along the building height are obtained from simultaneous surface pressure measurement in the wind tunnel. Subsequent wind-induced responses are calculated by direct time integration and modal analysis. This technique inherently accounts for any nonlinear mode shapes and readily handles the wind-induced response analysis of complex structures. Verification of the techniques is made by performing a comparison HFFB measurement. It is shown that for a building of ideal mode shapes, the surface pressure measurement and the time domain response computation result in similar spectra of the base moments and building responses as those from the HFFB technique. The developed time domain technique is then used to investigate the mode shape correction factors for force balance technique on buildings of non-ideal mode shapes. A parametric study is carried out to integrate the effect of non-ideality of mode shapes, vertical distribution of wind loads and masses along the building height on the mode shape correction factors used for HFFB technique. The results agree well with those from the literature. Tall buildings of complex shapes and structural systems, or uneven mass distribution patterns are becoming increasingly popular, which greatly complicates the performance assessment under extreme wind events. A number of building models are analyzed by a structural dynamics analysis software ETABS to investigate the influence of building mass distribution pattern and mass-rigidity- center eccentricity on the dynamic properties and the wind-induced responses. Results show that uneven mass distribution considerably influences structure stiffness and subsequently the natural frequencies of vibration. Response computation reveals the fact that lighter upper storey masses induce increasing excessive building vibration. At the same time, the mass-rigidity-center offset induces extra coupled building translational-torsional modes of vibration,
The Influence of Wind-induced Motions on the Performance of Tall Buildings
Author: John KilpatrickThe Influence of Wind-induced Motions on the Performance of Tall Buildings
Author: Effects of a Tuned Mass Damper on Wind-induced Motions in Tall Buildings
Author: Julien Alexandre Laurent CarlotPublisher:
ISBN:
Category :
Languages : en
Pages : 107
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.
Wind-induced Motion of Tall Buildings
Author: Kenny C. S. KwokPublisher:
ISBN: 9780784413852
Category : Architecture
Languages : en
Pages : 66
Book Description
This state-of-the-art report describes various facets of the human response to wind-induced motion in tall buildings and identifies design strategies to mitigate the effects of such motion on building occupants.
Building Motion in Wind
Author: N. IsyumovPublisher:
ISBN:
Category : Science
Languages : en
Pages : 124
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.
High-Rise Buildings under Multi-Hazard Environment
Author: Mingfeng HuangPublisher: Springer
ISBN: 9811017441
Category : Technology & Engineering
Languages : en
Pages : 251
Book Description
This book discusses performance-based seismic and wind-resistant design for high-rise building structures, with a particular focus on establishing an integrated approach for performance-based wind engineering, which is currently less advanced than seismic engineering. This book also provides a state-of-the-art review of numerous methodologies, including computational fluid dynamics (CFD), extreme value analysis, structural optimization, vibration control, pushover analysis, response spectrum analysis, modal parameter identification for the assessment of the wind-resistant and seismic performance of tall buildings in the design stage and actual tall buildings in use. Several new structural optimization methods, including the augmented optimality criteria method, have been developed and employed in the context of performance-based design. This book is a valuable resource for students, researchers and engineers in the field of civil and structural engineering.