Design and Theory of Passive Eddy Current Dampers in Building Structures

An eddy current damper (ECD) offers effective vibration suppression by dissipating energy through circular currents produced inside a conductor that is subjected to a varying magnetic field, running through the resistivity of the conductor. Due to its non-contact and fluid-free characteristics, an ECD does not add significant mass and stiffness to the structural system, and eliminates maintenance needs for tuning, leakage, etc. Unlike other viscous dampers used in building structures, an ECD works by producing a damping force that is a linear function of velocity. ECDs have been widely researched and used for various mechanical applications, but their implementation in building structures has been limited. The literature on the use of ECDs in structures has mainly focused on theoretical models and model validations to describe the damping mechanism; relatively little is known about the design practice involving ECDs. Utilizing finite element analysis, this study identifies key design parameters and the design process involving an ECD, based on electromagnetic theory and validated analytical models. The goal is enable design engineers to select and implement passive ECDs in building structures.