Mitigation of motions of tall buildings with specific examples of recent applications

Abstract

Flexible structures may fall victim to excessive levels of vibration under the action of wind, adversely affecting serviceability and occupant comfort. To ensure the functional performance of flexible structures, various design modifications are possible, ranging from alternative structural systems to the utilization of passive and active control devices. This paper presents an overview of state-of-the-art measures to reduce structural response of buildings, including a summary of recent work in aerodynamic tailoring and a discussion of auxiliary damping devices for mitigating the wind-induced motion of structures. In addition, some discussion of the application of such devices to improve structural resistance to seismic events is also presented, concluding with detailed examples of the application of auxiliary damping devices in Australia, Canada, China, Japan, and the United States.

A Cyber-Based Data-Enabled Virtual Organization for Wind Load Effects on Civil Infrastructures: VORTEX-Winds

“…Since the inherent damping in these structures cannot be engineered, reliance is placed on augmenting damping through auxiliary damping devices. Introduction of these devices leads to measurable and controllable levels of damping in buildings (Kareem et al, 1999). The Damping database is an initiative to provide users with on-line damping information for various full-scale building structures in terms of a query-based database module.…”

Wind-induced vibrations of buildings: role of transient events

“…In these events, as shown by this study, rapid changes in wind direction can cause dominant motions suddenly to switch their primary axes (see Figure 7) and stimulate significant amounts of companion torsion that, in the case of buildings with coupled modes, can lead to rapid increases in acceleration. Particularly since these situations involve torsional accelerations that have been noted to be especially disturbing to occupants (Kareem et al, 1999), they represent an in situ condition that has yet to be replicated by motion simulator studies used to define perception criteria. In fact, these events may constitute a missing element of current design practice to minimise perceptible motions, as anecdotal evidence indicates that thunderstorm events in particular, owing to their sudden onset and rapid changes in amplitude and direction, cause perception issues in tall buildings (Bentz and Kijewski-Correa, 2009a).…”

Investigation of PTMD System Affected by Parkfield Near-Field Earthquake

“…Furthermore, these structures are a place for comfort and convenience of people to live and work. Vibrations resulted from structural responses between 0.1g to 0.25g could disrupt the operation of the interested structure (Kareem, Kijewski, & Tamura, 1999). Some sensitive people even feel small accelerations as 0.05g (Kareem et al, 1999).…”

“…Vibrations resulted from structural responses between 0.1g to 0.25g could disrupt the operation of the interested structure (Kareem, Kijewski, & Tamura, 1999). Some sensitive people even feel small accelerations as 0.05g (Kareem et al, 1999). In this paper, the Pendulum Tuned Mass Damper (PTMD) system which is one of the common tuned mass dampers studied under the Parkfield 2004 with directivity earthquake at the most critical force applying angle.…”

“…Other common TMD systems are: Translational TMD, Active TMD and Semi active TMD. The reasons of choosing PTMD compared to the other types are its simple preparation and installation cost, simplicity of adding to existing in operation structures without spending much time, proper performance, simple set up, the absence of any external actuator which reduces the initial cost of installation and maintenance, no need to apply energy to the system by the actuator and eliminating the possible delay in active tuned mass dampers (Kareem et al, 1999). The semi active system as shown in Figure 1 has both advantages of the active and passive systems.…”