Performance-Based Placement Design of Tuned Electromagnetic Inertial Mass Dampers

Abstract

This paper presents a performance-based placement design method for the control of the earthquake responses of a multistory building using tuned electromagnetic inertial mass dampers (T-EIMDs). The T-EIMD consists of a ball screw mechanism, a gear, a flywheel, and an electric generator installed in a cylinder, and a spring element connected in series. The ball screw mechanism converts the axial oscillation of the rod end into the rotational motion of the internal flywheel and generates a large inertial force. The electric generator is turned by the rotation of the inner rod and generates a variable damping force that is controlled by the terminal resistance. The T-EIMDs are installed between adjacent floors of a building with steel chevron braces and function as large tuned mass dampers within the stories. The spring element has the function of tuning the natural period of the T-EIMD to the fundamental natural period of the building. In the present work, a design procedure for the story-wise placement of T-EIMDs is proposed to limit the peak story drift angles to a specified target value. The proposed procedure utilizes the expanded complete quadratic combination method that involves modal analysis with complex eigenvalue analysis and is able to determine the necessary story-wise distribution of inertial masses of the T-EIMDs in a building. Time history earthquake response analyses are carried out for multistory building models set up with the necessary number of T-EIMD units, and the results establish the effectiveness and the adequacy of the proposed performance-based placement design procedure.

Outrigger tuned inertial mass electromagnetic transducers for high-rise buildings subject to long period earthquakes

“…During seismic events, an external power source is not guaranteed, so the generated energy by the motor is of value to self-powered control, structural health monitoring, emergency power supply and so on. Similar energy harvesting devices employing the tuned inerter mechanism for civil structures have been proposed by other researchers [14,15]. In this research, to take full advantage of the TIMET on high-rise buildings, the outrigger damping system [16,17,18] is combined with the TIMET.…”

Experimental characterization and performance improvement evaluation of an electromagnetic transducer utilizing a tuned inerter

“…However, in these numerical simulation studies, energy loss occurring in the mechanical device was not considered, even though that could be a critical issue practically in the field of energy harvesting. A device with the same mechanism as the TIMET, named tuned electromagnetic inertial mass damper, has been introduced by Nakamura and Hanzawa (2017) independently from the authors, in which experimental studies were conducted. However, since the device was considered only as a structural control device, the power generation efficiency was not examined in the literature.…”

Performance-Based Placement of Manufactured Viscoelastic Dampers for Design Response Spectrum

“…A mechanical model for the VED was proposed using a non-linear four-element (NLF) model that comprises two non-linear dashpot elements and two non-linear spring elements (Nakamura and Kaneko, 1998). A placement-design procedure is proposed for the VEDs such that each peak interstory drift is limited to the specified value for a given design response spectrum (Nakamura and Hanzawa, 2002). The proposed design procedure has originality in the equivalent linearization of the VED based on the interstory drift constraint and the expanded CQC method in the peak response estimation.…”