An Energy Framework to Control Viscoelastic Semi-Active Devices in Plan-Wise One-Way Asymmetric Systems

This study proposes new strategies for the semi-active control of the dynamic response of a plan-wise asymmetrical structural system using viscoelastic devices. Different from some literature proposals, these innovative strategies are designed to be immediately interpretable, aiming to optimize the different terms of the energy balance equation through a set of closed-form analytical control algorithms to manage the properties of semi-active devices. Specifically, four algorithms have been developed to maximize the energy dissipated by the system or minimize the elastic energy, kinetic energy, and input energy. These algorithms have been tested through an extensive numerical investigation by modifying the main structural parameters of the asymmetrical system and considering 85 accelerometric input signals with different dynamic characteristics related to both far-field and near-fault records. The effectiveness of the four proposed strategies, aimed to modify the semi-active device properties, was evaluated by comparing the seismic responses of asymmetric systems, in terms of both relative displacement and energy components, with the regular configuration of semi-active devices (i.e., passive control) and other algorithms, such as “Kamagata & Kobori” and “sky hook” finalized, respectively, to manage stiffness and damping extra-structural resources. The results demonstrated the effectiveness of the proposed strategies, especially, in the presence of flexible systems and high-demanding near-fault seismic events.