Optimal tuning of SMA inerter for simultaneous wind induced vibration control of high-rise building and energy harvesting

This study proposes shape memory alloy based inerter combined with electromagnetic transducer for both vibration control of buildings and energy harvesting. The proposed device has non-linear spring made of shape memory alloy for its excellent load-deformation characteristics. The hysteretic behavior of this smart material is capable of dissipating significant amount of energy. The conventional viscous damping is also replaced by a motor, which offers flexibility in damping while converting the mechanical energy into power. The optimal performance of this device demands precise tuning of its parameters for vibration control of the building, which is exposed to random wind load. This, in turn, advocates for the solution of stochastic non-linear optimization problem, which is the main aim of this study. It is proposed in two steps i.e. adopt equivalent linearization for efficient input-output characterization followed by an ensemble surrogate analysis for stochastic response quantification. A seventy six storied benchmark building is used for numerical demonstration, which clearly establishes the superiority of the passive device for simultaneous vibration control and energy harvesting over the possible range of wind speeds. The results show that the ensemble surrogate model is very efficient to predict the responses compared to a single surrogate model. Overall the performance of the controller is impressive and can be adopted for further experimental investigation prior to its use in prototype buildings.