비고정 연결방식의 구체 감속기를 이용한 적층식 이산체의 제진 성능 평가

Abstract

This study proposes a method to improve the seismic performance of a stacked stone pagoda by applying a Ball Vibration Absorber (BVA) with a non-fixed connection. The governing equations of motion were derived by analyzing the structure's primary failure mode under seismic excitation and sliding behavior, and a numerical model was constructed. To verify the model's reliability, a shaking table experiment with a two-layer rectangular block structure was conducted, and the experimental results were compared with numerical simulations. Based on the validated numerical model, both artificial and real earthquake records were used for parametric analyses to determine the optimal design parameters that maximize the damping efficiency of the BVA system. The main findings of this study are as follows. First, when the difference between the rolling path radius and the ball radius is small, the damping performance of the BVA decreases. Still, this effect becomes negligible once the difference exceeds a certain threshold. Second, when the friction coefficient between the BVA container and the target structure is small, the non-fixed connection type exhibits superior damping performance; as the friction coefficient increases, its performance converges to that of the fixed connection type. Third, the damping performance of the BVA improves significantly as the mass of the ball increases. Fourth, the damping efficiency of the BVA is inversely proportional to the amplitude of seismic acceleration. However, its performance slightly weakens under strong ground motions; it still maintains a stable damping capacity.