Bio-Inspired Passive Optimized Base-Isolation System for Seismic Mitigation of Building Structures

Abstract

An energy dissipation mechanism of abalone shells, called sacrificial bonds and hidden length, is simulated and proposed to develop new strategies for base isolation. The concept of integrating this novel energy dispersion mechanism into a conventional linear isolator is proposed. A systematic parametric study is performed to evaluate the influences of the properties of both the isolation layer and the structure on the structural seismic responses to a series of earthquake records. Using the insights gained from the parametric study, an optimization procedure for designing such a bio-inspired isolator is presented based on the multiobjective optimization approach. To demonstrate the advantages of this idea, the optimized bio-inspired isolation system is numerically investigated by first comparing it with the passive isolators such as a high-damping linear isolator and a lead rubber bearing system. The proposed isolator is found to have superior performance to conventional passive isolation systems, especially in cases of near-fault earthquakes. Furthermore, the bio-inspired passive isolator shows comparable performance to a semiactive isolation system under the selected earthquake excitations.