A Study on the use of an Energy-Regenerative Tuned Mass Damper for Vibration Control and Monitoring of Base-Isolated Buildings

This paper studies the use of an energy-regenerative tuned mass damper (ER-TMD) to (a) passively control the displacement of superstructure of a two-degree-of-freedom base-isolated building model equipped with elastomeric rubber bearings and (b) simultaneously generate electric energy that can be used to power conventional sensors installed on the building to monitor its response during an earthquake. The proposed passive ER-TMD is composed of two parts: mechanical and electrical. The mechanical part consists of a moving mass (i.e., TMD mass) attached to the base floor through a linear spring-damper system, and the electrical part consists of two large permanent magnets, a rectangular air-core copper coil, and a harvesting circuit designed to maximize the electric power outputted from the proposed ER-TMD. The total damping coefficient of ER-TMD, obtained by adding up the damping effects of the mechanical and electrical parts, is variable and depends on the amplitude of vibration during the earthquake. A parametric study is carried out to find the optimum damping coefficient of proposed ER-TMD. The numerical results show that the proposed ER-TMD can limit the displacement of superstructure to a safe level while it is capable of generating an average electric power about 0.5W which is large enough to power a conventional accelerometer when the building is subjected to an earthquake with the intensity similar to that of maximum considered earthquake (MCE) as defined by ASCE 7-10.