为评价深厚软土场地地铁隧道内钢弹簧浮置板轨道的轮轨力及减振性能，遴选出满足地质条件相似、隧道埋深相同、列车行驶速度和载重一致三个前提条件的浮置板和整体式轨道，分别测试其垂向、横向轮轨力和钢轨变形，以及其钢轨、轨枕板和隧道壁的三向振动加速度时程，并展开时域和频域分析。结果表明：①浮置板会小幅增加垂向轮轨力，大幅增加横向轮轨力，且使轮轨力的低频准静态作用占比更大；②轮轨力的低频成分增加后引发钢轨的低频抖动，使钢轨的垂向、横向位移分别增大了2.4倍和4倍，且波动性更明显，对平稳行车将产生不利影响；③浮置板使隧道壁的横向、垂向振动加速度级均减小约5 dB，但纵向振级变化不大，与此同时浮置板自身的横向、垂向振动加速度级增加10~12 dB，证明浮置板有效阻隔了车轨振动能量；④软土场地内地铁隧道的横向、垂向共振频率约50 Hz，浮置板有效抑制了其共振现象，使分频振级减小10~18 dB，达到了特殊减振性能要求，说明低频轮轨力的增加对其减振性能的影响较小，钢弹簧浮置板在深厚软土场地仍具有适用性。

In order to evaluate the influence of steel spring-floating plate track on wheel-rail forces and its actual vibration damping effects in a deep soft-soil tunnel, steel spring floating plate track bed and ordinary integral track bed were selected to meet the three preconditions of similar geological conditions, the same buried depth of the tunnel, and the same train speed and load. The vertical and lateral wheel-rail forces and rail deformation were tested respectively, and the three-direction vibration acceleration time travel curve of its rail, sleeper plate and tunnel wall, expand the time domain and frequency domain analysis. The results show that: (1) the floating plate can increase the vertical wheel-rail force slightly, increase the transverse wheel-rail force greatly, and make the low-frequency quasi-static action of wheel-rail force take a larger proportion; (2) The incensement of low-frequency components of wheel-rail forces cause the low-frequency jitter of the floating slab, resulting in a significant increase in rail displacement and volatility, and its vertical and lateral displacement increased by 2.4 times and 4 times respectively, which will have an adverse effect on smooth running; (3) The transverse and vertical vibration acceleration levels of the soft-soil tunnel wall were reduced by 5 dB, and the longitudinal vibration changed little, while the transverse and vertical vibration acceleration levels of the sleeper plate were increased by 10~12 dB, which proves that the floating plate effectively blocks the vibration energy. (4) The transverse and vertical resonance frequencies of the tunnel are about 50 Hz, and the floating slab effectively suppress the transverse and vertical vibration levels by 10~18 dB, satisfying the performance requirements of special vibration reduction measures. It shows that the increase of low frequency wheel-rail force has little effect on the high frequency vibration isolation performance of the floating slab, and the steel-spring floating slab is also appropriate to soft-soil subway tunnels.

TB523

国家自然科学基金（52125803）；浙江省自然科学基金项目(LY22E080003)；浙江省省属高校基本科研业务费专项资金资助（SJLZ2022003）