Pareto-optimal seismic co-design of a novel integrated VibroHarvest system for long-period structures

Long-period structures are susceptible to resonance when subjected to ground motions with dominant frequencies below 1 Hz. This resonance can amplify seismic responses, compromising structural integrity. To enhance seismic resilience and promote energy sustainability, this study introduces an integrated VibroHarvest system (IVHS) that combines structural vibration control with energy harvesting, utilizing a piezoelectric nanogenerator. A multi-objective co-design optimization framework was developed to simultaneously minimize structural displacements and roof-floor accelerations, while maximizing the amount of harvested energy. A matrix-partitioning strategy was integrated into the solution scheme to ensure numerical robustness under strong electromechanical coupling. The dynamic performance of the IVHS was evaluated via time-domain seismic simulations. Additionally, global sensitivity analysis (GSA) was employed to identify the parameters that most significantly influence seismic response and energy-harvesting efficiency. Compared with conventional tuned viscous mass dampers (TVMDs), the IVHS reduces peak isolator displacement and roof-floor acceleration by up to 25.59% and 15.50%, respectively. Simultaneously, the system harvests an average power of 0.60 W (0.026–2.66 W under the tested conditions), which is sufficient to enable autonomous post-seismic monitoring and real-time damage evaluation without external power sources. Even the minimum output (∼26 mW) significantly exceeds that of typical piezoelectric harvesters. GSA based on Sobol’s indices reveals that load resistance and electromechanical coupling coefficients influence energy output. Conversely, TVMD damping coefficients and stiffness parameters predominantly influence vibration mitigation. These findings establish a dual-functional design framework for the development of resilient, energy-autonomous civil infrastructure. • IVHS reduces seismic displacement and acceleration by up to 25.59% and 15.50%. • IVHS generates over 25 mW power for autonomous monitoring. • Matrix partitioning ensures numerical stability under strong coupling. • Global sensitivity analysis reveals key parameters influencing response. • IVHS enhances seismic resilience and energy sustainability.