Abstract: In order to evaluate the particle damping double layer vibration isolation system comprehensively,a new vibration reduction effect evaluation method is proposed.This method defines the particle damping double layer vibration isolation effect index as the sum of the vibration level difference and particle damping insertion loss.The acceleration signal of the lower base,the middle layer raft and the upper unit of the double layer vibration isolation system under different vibration conditions is measured by experiments.The evaluation method is used for experimental analysis.The experimental results show that when the particle filling ratio is 70 %,the damping effect is the best,and the damping ratio reaches 33 % in the resonant frequency band.The particle damping improves the vibration reduction effect of the double layer vibration isolation system.The experimental results verify the effectiveness of the evaluation method.

Key words: particle damping, double layer vibration isolation, damping effect, vibration level difference, insertion loss, damping ratio