A Comparison between a New Semi-Active Tuned Mass Damper and an Active Tuned Mass Damper

Abstract

Reducing structural vibrations is one of the main concerns in structural control. Different control techniques are proposed for this purpose. Among the variety of control methods, semi-active ones are very attractive and beneficial in that they require minimum amount of energy but they are very capable to reduce structural displacements. In this paper, the behavior of a structure equipped with a new type of semi-active tuned mass damper called SADA-TMD is compared to the behavior of a structure equipped with active tuned mass damper (ATMD). SADA-TMD is a TMD equipped with semi-active damper actuator (SADA). This device can absorb energy transferred to the ordinary TMD during earthquakes and use it like an actuator; it can also dampen any part of this absorbed energy. For the purpose of comparison a multi story building has been modeled numerically. The performance of SADA-TMD and ATMD is controlled by fuzzy logic controller (FLC). Advantages of employing SADA-TMD to reduce structural responses are shown through illustrations and numerical results. However, the results come from applying SADA-TMD can be compared to that of active tuned mass dampers (ATMD), because SADA-TMD is a semi-active device, the power requirements is significantly lower than those of ATMD. It is worth to be mentioned that because SADA-TMD can work on battery power, it is more reliable than ATMD during strong earthquakes; because the source of energy which is necessary for active actuator could be failed during those earthquakes.