基于隔振器荷载特征的浮置板轨道定频隔振器设计研究

In this paper, a nonlinear floating-slab vibration isolator and its optimal nonlinear damper with constant natural frequency was proposed, based on the nonlinear vibration theory, to ensure operating stability of the train in the laying area of the floating-slab track. Firstly, the vibration isolation requirements of the floating slab vibration isolation system were determined,through the identification of the load characteristics of the vibration isolator for the floating slab track. Secondly, the stiffness curve of constant frequency nonlinear vibration isolation systemwith the constant natural frequency near any quasi-static load position, was designed, based on the dynamic characteristics of variable mass vibration isolation system. Then, the optimal nonlinear damping design for the constant frequency system was carried out, based on the characteristics of the stiffness curve of the constant frequency system and the influence mechanism of the damping coefficient on the vibration isolation performance of the nonlinear system. Finally, the optimal fixed frequency system was simulated and verified,based on the integrated simulation analysis model of vehicle floating slab track tunnel system. The results show that, compared with traditional floating slab system which adopt linear steel spring isolator, the constant frequency system has a better displacement control capacity,the dynamic displacement response of the slab can be reduced by about 8%. The constant frequency system can significantly reduce the acceleration response of floating slab, vibration acceleration effective value can be reduced about 46. 24%. The constant frequency system has a better vibration attenuation effect in all frequency band, Z weighting vibration level decreases by about 6. 26 dB.