Study on the vibration isolation performance of an open trench-wave impedance block barrier using perfectly matched layer boundaries

One of the problems associated with vibration pollution is ground vibration. In view of the isolation of objects protected from ground-transmitted vibrations, a novel type of vibration isolation barrier, an open trench-wave impedance block, is proposed. Based on the perfectly matched layer absorbing boundary, the two-dimensional finite element method in the frequency domain is used to investigate the vibration isolation performance of the open trench-wave impedance block barrier system for reducing the vibration generated by a vibration source. Firstly, the governing equation of the perfectly matched layer absorbing boundary is established in the frequency domain by using complex coordinate stretching. Secondly, using Galerkin approximation technology, the calculation formula of the second-order non-splitting perfectly matched layer with the displacement as the basic unknown quantity is given for the finite element method in the frequency domain. Finally, the influence of the physical parameters (modulus ratio between ground and wave impedance block), geometric parameters (dimension and layout of an open trench-wave impedance block barrier, including embedded length and width) and the load parameters (exciting frequency of the vibration source) on its vibration isolation performance is researched. The results show that the open trench-wave impedance block barrier system can provide a more flexible and efficient isolation barrier for ground vibration control.