RESEARCH ON THE VIBRATION MITIGATION AND ISOLATION EFFECTIVENESS OF TUBULAR

With the rapid development of urban rail transit, while it provides fast and convenient travel services, the environmental vibration induced by train operations has become increasingly prominent, drawing significant attention in both engineering and academia. To address the prediction and mitigation of train-induced environmental vibrations, this paper establishes a coupled analytical model incorporating the train, track, tunnel lining, half-space foundation, and vibration isolation barrier based on the wave function method. The theoretical solution for the environmental vibration caused by moving train loads under track irregularities is derived for a pipe-type vibration isolation barrier. On this basis, a systematic analysis is conducted on key factors such as train speed, track irregularity level, and barrier arrangement pattern. The results show that the burial depth of the isolation barrier significantly influences its vibration isolation performance; the closer the barrier depth is to the tunnel depth, the better the isolation effect. Horizontally arranged pipe barriers exhibit better vibration isolation performance than vertically arranged ones. Increasing the number of barriers and the barrier radius enhances the isolation effect, whereas the influence of barrier material properties on isolation performance is relatively minor. Furthermore, compared with a single barrier, optimizing the spacing between multiple barriers to form a multiple isolation system not only substantially improves isolation efficiency but also broadens the effective area of vibration attenuation. The findings provide theoretical support and design references for predicting and mitigating environmental vibrations induced by urban rail transit, offering significant engineering application value.