Blast wave attenuation of nonlinear meta-isolation system: Theoretical analysis and experimental validation

Abstract

In the field of protective engineering, wire rope isolators are usually applied in the isolation floor to mitigate the impact and vibration induced by explosive blast. In this paper, two kinds of meta-isolation systems were proposed and designed based on the local resonance, and investigated by means of theoretical analysis, numerical calculation and experimental research. First, the force-displacement hysteresis loops of the selected wire rope isolators are obtained by the cyclic loading tests, and identified by a mathematical model to make preparations for numerical calculation. Then, in order to discuss the influence of mass ratio, stiffness ratio and damping ratio on the shock isolation, the two-degree-of-freedom (TDOF) linear and nonlinear models are studied based on the mode superposition method and fourth-order Rugga-Kutta method respectively. Finally, the blast-induced ground shock experiments were conducted to evaluate the isolation efficiencies of conventional isolation systems and meta-isolation systems. The experiment results reveal that the isolation efficiency of meta-isolation system can increase by 10% points vertically and 16% points horizontally compared to conventional systems, which indicates that the meta-isolation system has great potential to be adopted in the engineering structures and provides a new idea and reference for protective engineering.