Viscoelastic coupling dampers (VCDs) for enhanced wind and seismic performance of high‐rise buildings

Abstract

SUMMARY As high‐rise buildings are built taller and more slender, their dynamic behavior becomes an increasingly critical design consideration. Wind‐induced vibrations cause an increase in the lateral wind design loads, but more importantly, they can be perceived by building occupants, creating levels of discomfort ranging from minor annoyance to severe motion sickness. The current techniques to address wind vibration perception include stiffening the lateral load‐resisting system, adding mass to the building, reducing the number of stories, or incorporating a vibration absorber at the top of the building; each solution has significant economic consequences for builders. Significant distributed damage is also expected in tall buildings under severe seismic loading, as a result of the ductile seismic design philosophy that is widely used for such structures. In this paper, the viscoelastic coupling damper (VCD) that was developed at the University of Toronto to increase the level of inherent damping of tall coupled shear wall buildings to control wind‐induced and earthquake‐induced dynamic vibrations is introduced. Damping is provided by incorporating VCDs in lieu of coupling beams in common structural configurations and therefore does not occupy any valuable architectural space, while mitigating building tenant vibration perception problems and reducing both the wind and earthquake responses of the structure. This paper provides an overview of this newly proposed system, its development, and its performance benefits as well as the overall seismic and wind design philosophy that it encompasses. Two tall building case studies incorporating VCDs are presented to demonstrate how the system results in more efficient designs. In the examples that are presented, the focus is on the wind and moderate earthquake responses that often govern the design of such tall slender structures while reference is made to other studies where the response of the system under severe seismic loading conditions is examined in more detail and where results from tests conducted on the viscoelastic material and the VCDs in full‐scale are presented. Copyright © 2013 John Wiley & Sons, Ltd.

Shaking table tests and numerical analyses of an RC coupled wall structure with replaceable coupling beams

“…The steel coupling beam with the central fuse had excellent energy‐dissipation capacity and exhibited a relatively low level of damage . Christopoulos et al developed a viscous coupling damper (VCD) with a replaceable shear‐critical structural fuse to accommodate the short span of the coupling beams. Nonlinear dynamic analysis indicated that fewer coupling beams were damaged or required repair due to the installation of VCDs, and analytical models of the VCDs as well as the tall shear walls with VCDs were proposed and verified .…”

Study of a new type of replaceable coupling beam in reinforced concrete shear wall structures

“…The replaceable part and the elastic parts were connected by bolts, which could be replaced readily after being damaged. Montgomery et al developed a viscoelastic (VE) coupling damper, which consisted of layers of VE material sandwiched between layers of steel plates. Nonlinear dynamic analysis of tall buildings incorporating VE coupling dampers demonstrated good performance under winds and earthquakes.…”

Development of a Multiaction Hybrid Damper for Passive Energy Dissipation

“…Hybrid passive control damper (HPCD) consisting of high-damping rubber damper in series with a buckling-restrained brace (BRB) was developed to dissipate multilevel seismic energy [12]. Christopoulos and Montgomery suggested that viscoelastic coupling damper (VCD) consists of VE material, steel plate, and anchor to reduce both the wind and earthquake response of tall shear wall buildings [13]. A hybrid damper which combines a friction damper and steel strip damper is proposed for improving the seismic performance of structures at multiple levels by Lee et al [14].…”