轨道交通高架桥梁振动阻抗及传递特性分析

Analysis on Vibration Impedance and Its Transfer Characteristics for Rail Transit Viaducts

列车荷载引发轨道结构及其下部桥梁结构振动,进而引发二次辐射噪声,其辐射噪声取决于桥梁的阻抗,一般桥梁阻抗越大,辐射噪声越小。就影响城市轨道高架桥梁二次辐射噪声的桥梁阻抗及振动传递函数进行建模和分析,讨论影响桥梁阻抗的因素,以期在今后的桥梁设计中考虑增大桥梁阻抗,从降低桥梁振动和减小辐射噪声的角度对桥梁设计进行优化。

Train loads induce the vibrations of track structure and its lower viaduct structure, further causing the re-radiated noise. The re-radiated noise depends on the impedance of the viaduct. In general, the greater the viaduct impedance, the lower the re-radiated noise. The paper established the models of impedance and v^ration transfer functions of the viaduct and analysed the influence factors of viaduct impedance. It suggested that the viaduct impedance should be increased and the design of viaduct should be optimized from the perspective of vbration reduction and diminishing re-radiated noise.