苏州地铁钢弹簧浮置板道床减振改造方案研究

Vibration Damping and modification Research of Steel Spring Floating Slab Track on Suzhou Metro

为解决苏州地铁4号线既有钢弹簧浮置板道床下穿地段振动及噪声较大等问题,采用现场轨道振动测试与有限元建模仿真的手段,对浮置板道床自身的振动传递特性以及减振优化改造方案进行分析,并提出改造方案。现场测试结果显示,钢轨传递至浮置板道床、隧道壁传递至地面的振动都存在振动放大的频率范围,而浮置板传递至隧道壁的振动存在明显衰减。针对减小钢弹簧刚度、减小扣件刚度、增加钢弹簧浮置板配重3种方案建立有限元仿真模型,研究浮置板道床减振优化效果。研究表明,采用增加钢弹簧浮置板配重的方式,能有效减小隧道壁的Z振级(2.9dB),以及有效控制钢轨位移(2.64 mm)和道床的位移(2.34 mm)。

Aiming at solving large vibration and noise in the section of steel spring floating slab track of Suzhou Metro Line 4,the field measurement and modeling analysis was used to analyze vibration transmissibility and modification scheme of steel spring floating slab,and a best modification scheme was proposed.According to field measurement,there is an enlarge region when the vibration transfer from rail to slab and from tunnel wall to ground,and there is also an attenuation when the vibration transfer from slab to tunnel wall.Three finite element model,including reducing steel spring stiffness,reducing fasteners stiffness and increasing counter weight of floating slab track,was established to analyze the effect of vibration damping optimization.According to the result,increasing counter weight of floating slab track was the most reasonable modification scheme,the vibration of tunnel wall was decreasing 2.9 dB,the rail displacement was controlled into 2.64 mm and the slab displacement was controlled into 2.34 mm.