高速列车阻尼喷涂式铝型材减振降噪特性试验

为探究某种阻尼材料对高速列车铝型材地板的减振降噪效果，以波纹状铝型材为基板，先后对其喷涂厚度为2 mm和4 mm的阻尼层，并在隔声室中进行空气声隔声及结构振动声辐射的测试及比对分析。结果显示，随阻尼层厚度的增加，铝型材的空气声隔声效果增加，尤其在500 Hz之后的中高频段；其中，2 mm阻尼层能在铝型材裸板的基础上使计权隔声量提高4.5 dB，阻尼层厚度增至4 mm，计权隔声量再提高2.4 dB。在100 Hz ～250 Hz，2 mm阻尼层对降低铝型材的振动声辐射水平起反作用，而4 mm阻尼层能够起到一定作用；在315 Hz ～400 Hz，阻尼层厚度对其振动声辐射几乎没有影响；500 Hz以上，随阻尼层厚度的增加，铝型材振动声辐射水平大大降低，其中，500 Hz、1 250 Hz和3 150 Hz 三个频段的降低量最为显著。

Experiments on Vibration and Noise Reduction Effect of Sprayed-damping Section Aluminum Applied to High-speed Trains

In order to clearly understand the effect of sprayed- damping on vibration and noise reduction of section aluminum floor of high-speed trains,a corrugated aluminum is used as the substrate and sprayed with 2 mm and 4 mm thick damping layers on it respectively.Then,the tests of the sound insulation,structural vibration and noise radiation are conducted in a laboratory.The test results show that as the thickness of the damping layer increases,the sound insulation effect increases,especially in the medium and high frequency range above 500 Hz.Sticking 2 mm thick damping layer on the corrugated aluminum floor can increase the weighted sound insulation by 4.5 dB compared with the corrugated aluminum floor without damping.When the thickness of the damping layer increases to 4 mm,the weighted sound insulation increases by 2.4 dB in comparison with 2 mm thick damping layer.In the range of 100 Hz -250 Hz,the 2 mm thick damping layer has negative effect on the reduction of vibration and noise radiation,but 4 mm thick damping layer has somewhat effect on noise and vibration reduction.In the frequency range from 315 Hz to 400 Hz,the damping layers of 2 mm and4 mm thicknesses have little sound insulation effect.When the frequency exceeds 500 Hz,with the increasing of the damping layer thickness,the vibration and noise radiation level of the section aluminum can be remarkably reduced,especially for the frequencies of 500 Hz,1 250 Hz and 3 150 Hz.