二维地基中空沟-波阻板联合隔振屏障分析

2D analysis of vibration-isolation efficiency of an open trench-wave impedence block barrier

针对地基隔振控制,提出了一类新型的空沟-波阻板联合隔振屏障,并对其隔振性能进行了数值分析。首先,利用复伸展坐标变换,在频域内建立了完全匹配层(perfect matched layer, PML)吸收边界的控制方程;其次,利用Galerkin近似技术,给出了以位移为基本未知量的二阶非分裂格式PML的频域有限元计算列式;最后,通过数值算例分析了空沟-波阻板联合隔振屏障的物性参数(地基与波阻板的模量比)、几何参数(空沟深度、波阻板深度)以及载荷参数(振动波频率)等对其隔振性能的影响规律。结果表明,空沟-波阻板联合隔振屏障结合了空沟和波阻板各自的优势,可以有效地控制不同频率振源引起的地基振动。

In view of the control of ground vibration isolation, a novel type of vibration isolation barrier, open trench-wave impedence block barrier, is proposed. The vibration isolation performance is analyzed by numerical simulation. Firstly, the governing equation of a non-splitting perfect matched layer(PML) absorbing boundary is established in the frequency domain by using complex coordinate stretching. Secondly, using Galerkin approximation technology, the frequency-domain finite element method formula of the second-order non-splitting PML with displacement as the basic unknown quantity is given. Finally, through numerical examples, the influence of physical parameters(modulus ratio of foundation to wave barrier), geometric parameters(trench depth, wave impedence block depth) and load parameters(frequency of vibration source) on the vibration isolation performance are investigated. The results show that the open trench-wave impedence block barrier can effectively control the ground vibration caused by different frequency vibration sources.