硬岩掘进机的动力吸振方案优化研究

针对某隧道掘进工程中硬岩掘进机(TBM)的振动进行了实地测量。通过现场测试的结果可以看出,TBM推进系统在整个工作过程中振动剧烈,且主梁振动加速度响应在15Hz附近处出现明显的峰值。为降低TBM推进系统的振动水平,提出利用动力吸振器对TBM系统的振动进行抑制的方案。传统动力吸振器必须要有足够的附加质量才能达到良好的吸振效果,然而,TBM系统质量巨大且安装空间有限,吸振器的附加质量很难做到足够大。为此提出应用杠杆机构来实现放大吸振器的附加质量的方案,并设计了适用于TBM推进系统的动力吸振器。通过TBM整机—动力吸振器动力学建模分析,得到系统的频率响应函数,进而利用定点理论求得吸振器的最优同调条件与最优阻尼条件,最后对比传统动力吸振器和质量放大吸振器对主系统的抑振效果。结果表明,优化后的质量放大吸振器在吸振效果上较传统动力吸振器具有明显的优势。

Optimization of Dynamic Absorbers of Tunnel Boring Machines

Vibration measurements of the thrust system of a Tunnel Boring Machine (TBM) are conducted at the construction site. The measurement results show the intensive vibration of the TBM during the tunnel boring process and that there is a distinct peak about 15 Hz. In order to suppress the vibration of TBM, a measure using dynamic vibration absorber (DVA) is considered. However, to ensure the vibration reduction effectiveness of the DVA, its mass is required to be large enough according to the principle of the traditional DVA design. Due to the tremendous mass of TBM and the limited available space for DVA installation, the mass of DVA is limited within a small range. In this work, new DVA with the application of the principle of the leverage is therefore proposed to implement the mass amplification effect. The dynamics equation for describing the motion of the considered mechanical system with this new DVA is developed, and the frequency response function is obtained. Furthermore, the stiffness and damping parameters of the proposed DVA are optimized using fixed-point design theory. Finally, the performance of the new DVA and the traditional DVA are compared, showing that the new DVA is performed much better than the traditional ones in terms of the vibration reduction of the trust system.