Performance of Floating Slab Track with Rubber Vibration Isolator

This study systematically introduces a floating slab track (FST) with rubber vibration isolator (RVI) and investigates its behavior in urban rail transit. The FEM is used for modal analysis to clarify the modal parameters of the FST system. A vehicle-slab track coupling sub-model and a tunnel-soil coupling sub-model were established and the propagation law was analyzed by calculating the vertical vibration accelerations beneath the shield wall as well as the vertical vibratory acceleration levels of the surrounding soil. A wheel-set drop test was carried out to verify the actual vibration isolation effect compared with the numerical models. The results reveal that the vibratory acceleration levels at the distance of 20m from the tunnel center-line basically meet the requirements for vibration in most areas of a city. The variation trend of the vibratory acceleration level measured in laboratory tests agrees well with the calculated values from the numerical simulation. The attenuation amplitude of the levels reaches 19.33dB with the German high disturbance irregularity and 20.05dB with the short-wave irregularity in the simulation, and the levels are reduced by 45-58dB in laboratory tests which demonstrate the FST with RVI performs well in vibration isolation.